Can anyone help identifying what I have? Thanks in advance.

 

407296 casting = Olds 71 72 8.5" 10 bolt rear end.

SA code = 2.73:1 gear ratio (I think).

 

Thank you Kenneth, now I know what I'm beginning with.

 

Sorry my bad, 1972 Cutlass Supreme 350 200-4r, stock rear end. I’m looking to upgrade the rear end before spring.

Arthur

 

Norm, the casting number identified it as a 1971-1972 Olds A body 8.5" 10 bolt rearend, which is independent of what vehicle it currently calls its residence (this rearend would fit under any GM A-body car from 1967-1972). Note that the CSM does not provide this information.

 

And ... sometimes the year does not make any difference since MANY many of these Muscle cars have been so mucked up with many owners original parts are RARELY in the cars anymore...especially rear ends.
It does help to have AS MUCH info as possible, so you are correct year, casting numbers, pictures (all powerful) are all pluses to have for IDing the parts...
JD
Jim