It'd make a great restoration project, and a lot of part can be had to 'sup up CJ2's and CJ2A's. They make replacement aluminum bodies, and you can punch out the sides of the engine compartment to cram in a V-8 smallblock. They don't weigh anything, in fact one of the original design specs was for it to be able to be literally lifted over many obstacles by the crew and passengers. The only cons are a very short wheelbase making for tough times over large obstacles, and scarcity of OEM parts. Aftermarket and custom parts are easy since the design is about as dirt simple as it comes. The axles you mentioned are only worth something for a restoration or a collector. The engine depends on what kind. There are many kinds of jeep engines, so it may or may not(probably may not) be a good substitue for the stock 4 banger.