[factorystock]

Since you have a c-20, you are probably interested in the 8 lug Dana 60. It was a crap shoot, you really dont know what you'll find under a 3/4 ton Chevy from 68-72, unless it was a BB, which had a 3.54 Dana standard. I would say most coil 3/4 tons used eatons while most leaf spring 3/4 tons used Dana. but not the rule. The real question is why did GM use both brands with the same ratios (4.10 vs. 4.11) and (4.56 vs 4.57)? The mystery ended in '73 when Chevy stopped using both and went with there own "corporate" 3/4 ton rear end.