I would have to find my receipts to be exact, but I think I've got $2700 into my D60. Bought the axle off of Craigslist for $100 and reused the ring gear as it was in good shape and the ratio I wanted. Bought everything else from Doctor Diff and had Warren Gear and Axle assemble it all. Included an Explorer rear disc setup.
I spec'd mine out with Dr Diff and it comes to $2,690.00,
Unfortunately I didn't order it last week and they're closed until Aug 9th for vacation now, Looks like the Dream Cruise and probably Hines Drive is out, again...