Right on man sounds like a cool project.
I think the straight axle is a good swap because you rid of the cv's and all the week sh*t that would break under hp or big tires for sure. What are you going to do about the 5 lug bolt pattern?

(Update)
Google searched and found this in a forum.

I did a Dana 44 out of an 89 Wagoneer as they are stronger and are also 6 lug rather than 5 x 4 1/2.
Rusty's Offroad sells the upper control arm brackets needed to attach to the differential to make it work and also the spring buckets and shock perches pre-fabbed. All you need to do is find a buddy that's good at welding and you can have it setup pretty easily.