If there is a place near you that can narrow a D60 that's by far the cheapest and best way to go. Get a truck one with either a 3.54 or 4.10, get a set of the correct length axles and the differential unit of your choice from Dr. Diff and have at it. The end cost will be the same as the 8 3/4 or the 9.25 by the time you fix them and you'll never do anything to the D60 after you bolt it in.

Sheldon