Previous owner had stripped entire drivetrain. He did stick a 3.08 gear, 8.2" Nova rear end back in it, after cutting the spring perches off! So I figured the 3.08 geared 8.5" would be my cheapest easy solution. And if I decide to swap in a 396 at some future time, the stronger rear end is already there. For now I'm building for an economy car. 3.08 gear and 0.64 overdrive equal 1.97 final drive. Hoping that will get some MPG's.