Broke down the vin on my 1970 el co and it has the custom V8 number or letter. Does that mean its an SS or custom ordered by someone?

yes..I have a "Custom" classic witch is one step from an "SS"..:beer:

I dont understand. So the vin wont tell you if its an SS?

Just a model designation... like LS or LT is today.

The "Custom" was one step up from the base model, and you had to have the custom to upgrade to the "SS" package. Yours could be an "SS" if it has all of the SS trim, it's real hard to prove either way.

I agree with moterhead, the only way to find out if its a real ss is to find the build sheet.

How do you get a build sheet, order it from chevy? Problem is this cars gone through a few phases, was dragged hard from what I understand. Guy I bought it from said it did have an SS grill but it was stolen. I know it doesnt have the original motor. Whether it is or isnt an ss isnt that big a deal. It would just be nice to know.

No build available anywhere today. The build sheet was a 8x11 computer print out used on the assembly line to instruct workers on what parts to use to assembly the car. Dozens were used in all the plants work stations and sub-assembly lines. Some would get hidden in the car by carpet, seat covers, door panels etc. Normally workers were supposed to tear off the sheet once the component was installed but the speed at which they were being pushed made many just ignore them and some would eventually get left in the car hidden from view. There is no guarantee you will find one, especially if the car has been hacked up by previous owners.

Adding SS trim is easy to do so from your description its likely nothing if left to find and they only way you can ever determine if the car is an SS is with some original paperwork dating back to when the car was sold new.