on the novas all 75's had the 8.5 according to this page http://novaresource.org/axle.htm does your skylark have the v6 or the straight 6 chevy engine my 76 has the 7.5 with the 231 v6(i need a 8.5 rear) you can look at the housing the 8.5 has two bumps on them as shown here http://www.stevesnovasite.com/forums/showthread.php?t=131506 i hope this helped scott
If you want an 8.5 for your car Scott, get one from a 75-79 Seville, they all had 8.5 rears and some had rear disc brakes as standard....you will have to change the bolt circle pattern as they use a 5" bolt circle while you want a 4.75" bolt circle.....or just use the 5" bolt circle rims....real cheap way to add disc brakes for the rear.
every 1975 should still have the 8.5 standard. pretty sure the 1976 -1979 were 7.5 if the engine was a 6 cylinder in the chevy buick olds or pontiac. Only the v* cars got the 8.5 in 1976 1977 and I think in 1978 1979 only the v8 chevy cars got the 8.5 NON of the buick olds or pontiac got the 8.5 because they only offered 6 cylinder motors...NOT sure about that though. Jim I AM sure about the v8 cars getting the 8.5 10 bolt for sure.... Oh and the picture is a 10 bolt 8.5 rear you listed.
