I scored a couple of Dana 60 truck rears off craigslist for cheap. Bought some parts from Dr. Diff and used gearsets bought from members here. Have a friend that has the bearing cups, setup shaft, and jig to narrow the housings. Set them up myself...strong rear for cheap.

CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax