[Formulabruce]

Originally Posted by njsteve

The original 5 leaf, springs were from the 1975, 2.56 rear that the car came with originally. The 1980 rear came from an 80 T/A. I was thinking that the spring perches were taller on the 2.56 rear to accommodate the taller spring pack?

I have never seen a 75 bird with 5 leafs, BUT ALL the Camaros except the Z had 5 leafs. thats the big difference between the rears, as you said taller perches.
I have a 1980 WS-6 rear in one of my cars, and its a 4 leaf perch. Just checked a '79 I have, 4 leaf.
2.56 with 5 leafs in '75. I would have never guessed Interesting!