[Spblack]

I know a few people have been having a difficult time identifying the year models of their Camaro subframes that are installed on their truck. I spoke with a Camaro parts dealer and this is what he gave me for identifying your front end. Hope this helps.

FB235 1-5/8
FB295 1-1/4
FB329 1-1/8
FB330 1-5/8
FB331 1-7/8
FB422 1-5/16
FB424 1-5/16

All measurements are rough / approximate done with a measuring tape.

Generally speaking, 70-72 cars used 4-FB329 for the upper and 2-FB235 and 2-FB295 for the lower.
73-74 cars changed the lowers to FB330 and FB331.
75-79 cars used 2-FB329 and 2-FB422 uppers, and 2-FB330 and 2-FB331 lowers.
80-81 cars were the same as 75-79 but the upper rear changed from 2-FB329 to 2-FB424.

Also, look at the outer tie rod ends.
70-74 cars were about 6-5/8 inches long.
75-81 cars were about 9 inches long.