Lee,If you have some pics and if not much trouble that would help. Would the difference be in the bumper mounting hole locations? Alternate plan is to salvage the good firebird upper tail light portion and use a good used or repop camaro section if it would work as a good used complete firebird tailpanel seems to be elusive.
David
http://FirstGenFirebird.org/show/closeup.mv?CarID=571 If i don't get this car back on the road soon i'm gonna go postal! On a quest for FGF knowledge 1968 Pontiac Firebird Convertible 1969 Oldsmobile Cutlass "S" Convertible *Sold*