R and R ing the Gage pod or replacing Idiot lights with Gages in a 1983 through 1988 El Camino. (may apply to others as well)
I will only go into the mechanical process of removing and replacing the pod as several other people have covered the need for the required circuits and senders and gages.
Follow these steps in this exact order. You cannot change the order and expect it to work.
1) Remove 6 Phillips head screws in the gage pod cover. Two on the front midway between the top and the bottom, two under the top lip, and two on the bottom under the edge. I have left the bottom two out on mine because they add no strength and are difficult to get to.
2) Remove the cover and put it aside
3) Remove 3 screws in the light switch mount and dismount the switch from the plug and put it aside.
4) Using an extension and 1/4" drive socket remove the left side air conditioning duct being careful to pull the duct out as the screw loosens so that it stays in the duct and doesn't drop into the dash. Set the duct aside with the screw in place.
5) Using a small screwdriver and holding the knob with your left thumb and forefinger, loosen the screw that holds the knob on the clock adjuster shaft (if you have a clock) again, pulling the knob back as the screw loosens so that you don't drop that little bitty screw on the floor where you cant find it. Set it where it wont get lost or bumped onto the ground.
6) Now. loosen the screws that hold the clear plastic cover over the gage mask and remove it, set it aside.
7) Now start being very careful around the gages as the plastic needles get very brittle from being in a hot cab for years. Don't touch them!
8) Remove the two screws that hold the auto transmission indicator in. It is just below the speedometer.
9) After removing the screws you can wiggle it around and out from under the "mask" but it will still have a small cable connected to it that is activated mechanically by the gear shift lever. Remove this cable from the indicator and remove the indicator and put it aside. This has to be done before the mask is removed as it goes through a slot in the mask.
10) Now remove the screws that hold the gage mask in place, remove it and set it aside. You will be painting the blue side of it with silver paint later. Don't forget to do this before putting it back so the night time lighting will be bright enough to see the gages.
(If you already have gages and are only replacing one, this is as far as you will have to go. By removing the mounting screws you can now remove gages so that they can be repaired or replaced.)
11) Now we are ready to remove the "pod".
sheet metal nuts at each corner of the pod. The upper right one has to be done with a 1/4" extension and ratchet wrench by reaching through the hole in the light panel that was made for just this operation. Once it is loose but not off. stop and using your left index finger reach back behind the light panel and hold the edge of the sheet metal nut so that it doesn't slip out of the socket. If you let it slip out when loose it will fall behind the dash and you may never see it again. Its a little tricky to withdraw the extension with your finger on the socket and then finagle it through the hole in the lamp panel, but is not difficult. The upper left one is not at the corner, but is above the speedometer. This is unfortunate as otherwise you could remove the pod without removing the clear front and mask. The other two nuts are easy to remove at the bottom corners.
13) Now, with your left index finger, reach through the hole where the air conditioning vent was and behind the speedometer. You will just barely be able to feel things. If you have a speedometer sensor on the back of the speedometer its a little more difficult, but its still possible. Feeling with the outside of the index finger, find the speedometer cable. Then move your finger toward yourself along the bottom of the speedometer cable until you feel a metal "ring" that is around the cable. Press this toward yourself and pull lightly on the pod toward yourself and the speedometer cable will release from the pod. NOW...DO NOT pull the pod off just yet.
14) Check and see that the transmission indicator cable will not snag anywhere and pull the pod toward yourself until the plug-in connector on the lower right back side pulls out. You can now pull the pod out but be careful as the speedometer sensor cable will still be connected. If you have removed or will be removing the computer you can remove the speedometer sensor from the speedometer and remove the pod. I folded the thing back up and pushed in back into the dash just in case I might find a use for it in the future. If you need to have it for the computer, I would cut the two wires about 6" from the sensor and put in a two pin PokHom connector so that every time you remove the pod you can disconnect it easily without removing the sensor from the speedometer. AND, I can guarantee you will remove the pod several, maybe as many as 10, times during this operation to install gages. I did.
15) Now you are ready to remove the idiot lights and all the instruments so that you can replace the printed circuit board with one for use with the gages.
16) If you don't have a printed circuit board for the gages, it is possible to use wire in its place. BUT don't attempt this unless you are familiar with reading schematics and doing electronics wiring. Its not a tough circuit to duplicate if you know what you are doing but if you don't you wont be able to do it without getting some training FIRST.
17) There are now several things you may want to do before reassembly that are not related directly to the gage installation but are easy to do now and not easy to do when you have it all back together and decide you wish you had done them.
18) Now is the perfect time to pull the speedometer cable out of its housing and lubricate/replace it if it is binding and making a "wavy" speedometer needle or is making that "rrrump...rrrump...rrrump" noise.
19) Before replacing the pod after installing your gages and circuit board you want to decide if you want the temp gage to deflect to the right when turning the key to the "start" position. Mine does and I consider that a test of the gage. It wont hurt the gage. But if that will bother you, you can cut the green wire, from pin 3 of the back plane connector, that goes to the ignition switch. There are two green wires from that connector, one to the temp sender and one to the ignition switch. The one to the ignition switch was used as a "lamp test" by grounding when the key is in the start position.
20) Check the connectors in the plug and make sure none are bent or displaced. You may also want to clean the contacts with some contact cleaner. The plug can be removed from the plastic panel by pressing in on the end of the plug to remove it.
21) Place a piece of duct tape over the sharp metal arch that goes over the steering column. It can touch and destroy a printed circuit board if the pod is pushed back too far. The tape will insulate it from the circuit if you push too hard.
22) Cut a small block of wood to insert between the plastic panel that holds the plug and the metal support structure. This panel tends to deflect forward as you push the pod back on and after years it may get to where it wont make good contact to the pod. The piece of wood should be just big enough to fit snuggly behind the upper left corner of the plastic panel and the metal support behind it. This will hold it from deflecting as much and because it is snug it wont fall out. If you make it too big you wont be able to push the pod all the way back!
23) Now remember the paint job I told you about? Get that gage mask that is black on the front and blue on the back. Mask the holes so that paint wont spray through and onto the black front area. Spray the blue (back) side with silver paint. This will increase the reflectivity so that you can see the gages at night. The idiot light panel had a lower light intensity than the gage panel. If you get some over spray you can always re spray the front with flat black.
24) Now the four main points to remember when you are replacing the pod:
a) Reassembly is the exact reverse of the removal process. (Famous last words)
b) Make sure you have fished the transmission indicator cable back through the hole where it can be reattached to the indicator in the next steps.
c) Make sure you have reattached the speedometer sensor if you are going to need it.
d) Make sure that as you put the pod back in you use your left hand fingers to align the speedometer cable with the back of the speedometer.
25) Now as you put the pod back in if it is aligned with the four studs that hold it in place it will automatically be aligned with the back plane plug. You may have to reach back behind the speedometer to give the cable a nudge onto the speedometer, but mine just clicked right into place as the pod was pushed back.
The rest is handled by working backwards up this list till the front panel is once again replaced.
My luck was that most of these 25 steps were learned one at a time as I removed and replaced the pod for each learning experience. Several times I had it almost back together only to remember that I had neglected to reattach the speedometer cable. Once I pressed back too hard and burned up several traces on the printed circuit. The final (I thought) time I had gotten everything right and found I had not wired the tempo gage correctly. The silver paint, wooden block, and lubing the speedometer cable hints all were "take it apart again" learning processes.
I hope this saves someone a few hours as my installation took 7 hours.
I will only go into the mechanical process of removing and replacing the pod as several other people have covered the need for the required circuits and senders and gages.
Follow these steps in this exact order. You cannot change the order and expect it to work.
1) Remove 6 Phillips head screws in the gage pod cover. Two on the front midway between the top and the bottom, two under the top lip, and two on the bottom under the edge. I have left the bottom two out on mine because they add no strength and are difficult to get to.
2) Remove the cover and put it aside
3) Remove 3 screws in the light switch mount and dismount the switch from the plug and put it aside.
4) Using an extension and 1/4" drive socket remove the left side air conditioning duct being careful to pull the duct out as the screw loosens so that it stays in the duct and doesn't drop into the dash. Set the duct aside with the screw in place.
5) Using a small screwdriver and holding the knob with your left thumb and forefinger, loosen the screw that holds the knob on the clock adjuster shaft (if you have a clock) again, pulling the knob back as the screw loosens so that you don't drop that little bitty screw on the floor where you cant find it. Set it where it wont get lost or bumped onto the ground.
6) Now. loosen the screws that hold the clear plastic cover over the gage mask and remove it, set it aside.
7) Now start being very careful around the gages as the plastic needles get very brittle from being in a hot cab for years. Don't touch them!
8) Remove the two screws that hold the auto transmission indicator in. It is just below the speedometer.
9) After removing the screws you can wiggle it around and out from under the "mask" but it will still have a small cable connected to it that is activated mechanically by the gear shift lever. Remove this cable from the indicator and remove the indicator and put it aside. This has to be done before the mask is removed as it goes through a slot in the mask.
10) Now remove the screws that hold the gage mask in place, remove it and set it aside. You will be painting the blue side of it with silver paint later. Don't forget to do this before putting it back so the night time lighting will be bright enough to see the gages.
(If you already have gages and are only replacing one, this is as far as you will have to go. By removing the mounting screws you can now remove gages so that they can be repaired or replaced.)
11) Now we are ready to remove the "pod".
sheet metal nuts at each corner of the pod. The upper right one has to be done with a 1/4" extension and ratchet wrench by reaching through the hole in the light panel that was made for just this operation. Once it is loose but not off. stop and using your left index finger reach back behind the light panel and hold the edge of the sheet metal nut so that it doesn't slip out of the socket. If you let it slip out when loose it will fall behind the dash and you may never see it again. Its a little tricky to withdraw the extension with your finger on the socket and then finagle it through the hole in the lamp panel, but is not difficult. The upper left one is not at the corner, but is above the speedometer. This is unfortunate as otherwise you could remove the pod without removing the clear front and mask. The other two nuts are easy to remove at the bottom corners.
13) Now, with your left index finger, reach through the hole where the air conditioning vent was and behind the speedometer. You will just barely be able to feel things. If you have a speedometer sensor on the back of the speedometer its a little more difficult, but its still possible. Feeling with the outside of the index finger, find the speedometer cable. Then move your finger toward yourself along the bottom of the speedometer cable until you feel a metal "ring" that is around the cable. Press this toward yourself and pull lightly on the pod toward yourself and the speedometer cable will release from the pod. NOW...DO NOT pull the pod off just yet.
14) Check and see that the transmission indicator cable will not snag anywhere and pull the pod toward yourself until the plug-in connector on the lower right back side pulls out. You can now pull the pod out but be careful as the speedometer sensor cable will still be connected. If you have removed or will be removing the computer you can remove the speedometer sensor from the speedometer and remove the pod. I folded the thing back up and pushed in back into the dash just in case I might find a use for it in the future. If you need to have it for the computer, I would cut the two wires about 6" from the sensor and put in a two pin PokHom connector so that every time you remove the pod you can disconnect it easily without removing the sensor from the speedometer. AND, I can guarantee you will remove the pod several, maybe as many as 10, times during this operation to install gages. I did.
15) Now you are ready to remove the idiot lights and all the instruments so that you can replace the printed circuit board with one for use with the gages.
16) If you don't have a printed circuit board for the gages, it is possible to use wire in its place. BUT don't attempt this unless you are familiar with reading schematics and doing electronics wiring. Its not a tough circuit to duplicate if you know what you are doing but if you don't you wont be able to do it without getting some training FIRST.
17) There are now several things you may want to do before reassembly that are not related directly to the gage installation but are easy to do now and not easy to do when you have it all back together and decide you wish you had done them.
18) Now is the perfect time to pull the speedometer cable out of its housing and lubricate/replace it if it is binding and making a "wavy" speedometer needle or is making that "rrrump...rrrump...rrrump" noise.
19) Before replacing the pod after installing your gages and circuit board you want to decide if you want the temp gage to deflect to the right when turning the key to the "start" position. Mine does and I consider that a test of the gage. It wont hurt the gage. But if that will bother you, you can cut the green wire, from pin 3 of the back plane connector, that goes to the ignition switch. There are two green wires from that connector, one to the temp sender and one to the ignition switch. The one to the ignition switch was used as a "lamp test" by grounding when the key is in the start position.
20) Check the connectors in the plug and make sure none are bent or displaced. You may also want to clean the contacts with some contact cleaner. The plug can be removed from the plastic panel by pressing in on the end of the plug to remove it.
21) Place a piece of duct tape over the sharp metal arch that goes over the steering column. It can touch and destroy a printed circuit board if the pod is pushed back too far. The tape will insulate it from the circuit if you push too hard.
22) Cut a small block of wood to insert between the plastic panel that holds the plug and the metal support structure. This panel tends to deflect forward as you push the pod back on and after years it may get to where it wont make good contact to the pod. The piece of wood should be just big enough to fit snuggly behind the upper left corner of the plastic panel and the metal support behind it. This will hold it from deflecting as much and because it is snug it wont fall out. If you make it too big you wont be able to push the pod all the way back!
23) Now remember the paint job I told you about? Get that gage mask that is black on the front and blue on the back. Mask the holes so that paint wont spray through and onto the black front area. Spray the blue (back) side with silver paint. This will increase the reflectivity so that you can see the gages at night. The idiot light panel had a lower light intensity than the gage panel. If you get some over spray you can always re spray the front with flat black.
24) Now the four main points to remember when you are replacing the pod:
a) Reassembly is the exact reverse of the removal process. (Famous last words)
b) Make sure you have fished the transmission indicator cable back through the hole where it can be reattached to the indicator in the next steps.
c) Make sure you have reattached the speedometer sensor if you are going to need it.
d) Make sure that as you put the pod back in you use your left hand fingers to align the speedometer cable with the back of the speedometer.
25) Now as you put the pod back in if it is aligned with the four studs that hold it in place it will automatically be aligned with the back plane plug. You may have to reach back behind the speedometer to give the cable a nudge onto the speedometer, but mine just clicked right into place as the pod was pushed back.
The rest is handled by working backwards up this list till the front panel is once again replaced.
My luck was that most of these 25 steps were learned one at a time as I removed and replaced the pod for each learning experience. Several times I had it almost back together only to remember that I had neglected to reattach the speedometer cable. Once I pressed back too hard and burned up several traces on the printed circuit. The final (I thought) time I had gotten everything right and found I had not wired the tempo gage correctly. The silver paint, wooden block, and lubing the speedometer cable hints all were "take it apart again" learning processes.
I hope this saves someone a few hours as my installation took 7 hours.