[texasred]

I think I found an answer or two...but only by deduction. These are NOT proven theories!

I picked up an early 72 build (Jan 72) parts car (thanks again, certified!). The upper tail lights have the "flat" fins and the lower ones have the "concave" fins.

Sometimes, there are minor mods during a model year run. Perhaps they changed the design slightly later on in the model year, which would explain the same P/N for different looking tail lights.

Alternatively, maybe they came from a different factory that used a different casting mold.

Either explaination fits...YOU BE THE JUDGE!

C.J.