Junyard Dana 60.

I concern over using the original axles because of the register for the center bore of the wheels.
Most 5x4.5 wheels have a 3.3 inch center bore, where 5x5.5 has about 4.25 center bore.

I would consider contacting one of the alxe suppliers (Strange, Moser, Mark Williams, etc) and have some axles built in the 5x4.5 pattern.

Easiest would probably be as mentioned, have the truck ends cut off and mopar ends welded on, so you have the smaller brakes, etc.