I've heard of early 70s stock 12 bolts fitting in 3rd gens with little modifacatoin and holding up for years. in fact there is a local guy that I know of around here with a 82 big black camaro runing 10s which had stock 12 bolt for 6 years till it broke, pretty impressive....

anybody have any input about this?

 

I can't think of any way you'd get one to fit with only "little modification".

 

The 2nd Gen cars had leaf springs if I recall right, and no torque arm, that would fall under major modification if you ask me. You can geet a custom built 12 bolt for these cars, but they arn't cheap. The guy either bought it with that custom rear in there, or lied to you.

 

The only way you are gonna find an F-body 12 bolt rear is if you find a '70 Z28, SS 396, or Trans Am.

1970 was the only year they got a 12 bolt rear end. 1971-81 was all 10 bolt rears. They are better then '82-92 10 bolt rears though, because IIRC, they are quite a bit bigger.

 

8.5" to be exact.

12 bolts are 8.875 IIRC.

A 8.5" 10 bolt is plenty strong, but you still have the torque arm, spring mounting issues.

 

A 68-72 A-body differential is the same width as a 70-81 F-body differential. Weld spring perches & shock mounts on and you're good to go if you have a second gen.

Too much fabrication required to put one in an 82-92 F-body.