Hello: I'm helping a friend setup his gears on his 10 bolt rear axle. It's a pontiac firebird 1979. Can you believe he had 2.43 gears!!!? /forums/images/graemlins/shocked.gif The pinion was almost larger than the ring. We're installing a set of used 3.73 gears I bought from Mudzer a long time ago but that I never installed because I got a couple of 14 bolt / Dana 60 axles for $500. Attached is a drawing of what we were able to achieve reusing the shims on the old gears. According to a manual on Randy's R&P, when setting used gears, we should care more on the coast side than the drive side. We feel that the coast side is better than the drive side. If we try to improve the drive side, we're sure we'll ruin the coast side. Please give us your comments. Thanks!