Got the D60 today. Everything seemed nice and tight. Hubs worked good. Didn't pull the cover 'cause it was sleeting, I was way late and didn't want to BamBamBlazer's family to have to wait at the truck stop we met at any more, and I couldn't really get it to balance on the pinion yoke so I could pull the cover without making a mess of the back of their truck.
According to BillaVista's BOM decoder it is a '82-'87 K30 axle with the big 35 spline inners and a 4.10 diff. Also has Superwinch INTERNAL hubs, a very beefy tie rod and crossover reverse high steer arms. Pics as soon as we get daylight and no rain at the same time.
Thanks for all your help guys. And thanks BamBamBlazer!