I'm pretty sure that any Chevy 70+ to 78/79 Dana 44 would be a bolt in swap, or a D60 to 87-ish if you want to go big. I know that Chevy had disc brakes in 73 with the body style change, but haven't looked under many 70-73 vintage 4x4 trucks. There may be difference in the spring pad widths, so measure there. Second, I did not list the Corporate 10-bolt, but these may fit too.

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1987 Raider - Roxy
1988 Mighty Max 2.6L Turbo - Pearl
1997 Mountaineer V8 - Freddy
2000 Excursion V10 - Freya