ZB3
A good combo you might look at would be a 70s Camaro/Nova. This is a good rear-end for use in an AD truck, the ratios are commonly 2.73-3.73, with higher gears available and they are the correct width for your truck. They have leaf springs, but the perches won't work with your springs. I bought a leaf spring set from Total Cost Involved. It was an easy bolt-in. Good luck.
