For this one, do I go in from the dash? For all I know, it has leaked into the passenger compartment ever since I got it (not too long ago). There is duck tape involved, as the A/C is disconnected in sort of rough fashion. I think the switch from A/C to heater is duct taped to open to heat. Any thoughts over and above the Haynes manual? Just order the part and go to it perhaps? Looks like more than one day for me...
Thanks!

P.S. I hope to post a few pics with progress on the floor pans.
We had a good rain last week, and *finally* no water came in anywhere! Which is good timing, as snow is forcast for next week.

Oh yeah, I also got to wonderin
if I have radiator fluid dripping down into the firewall insulation on the passenger side, can I be for sure that I need to replace the heater core as long as I am sure hose connections are good?

Thanks again.
J

According to the 74 Service Manual, the heater core is installed in the air distributor under the dash. You remove the nuts from the studs that hold the air box to the firewall from the engine side of the firewall after the obvious of draining rad, removing heater hoses and plugging the tubes from the core so you don't dump antifreeze on the floor when you remove the box from under the dash. Be careful to not bend the cables which will have to be disconnected as you drop the box. Looking at mine, it looks like a real pain in the neck. Some of the boys will think this is heresy, but have you thought about putting some stop leak in it and running the heater full bore for a while to see if that stops the leak? It's cold up there, now. As to your 2d post, it seems to me if you're getting antifreeze inside the car, it has to be the core, but it may be just a pin hole. Also note that if you have factory air, you have to loosen the inner fender skirt to get to the lower right hand stud on the box and have to remove the under dash tubes, etc to get the box out. Good Luck.

Good to hear from a fellow 4th Gen Ow,
I picked up some prestone plugger and a hydrometer
to make sure I got a good water/coolant mix
The fluid looks clean inside, and the radiator is pretty new.

So hope to get to it soon.
Thanks, I'll post back how it goes!
J