I vote build the uhaul. Convert it to 4x4. But don't rob the parts off the crew cab. It's just so nicely done. Build your uhaul, remove top on crew and you have a nice truck and an expo rig.
Well, you got my .02. I'd run the crew cab. But if you decided to run the U-haul it seems to me it would be far simpler to use the 5 spd and t-case from the crew cab. You'll need the transmission crossmember and the front shaft should work. You've got the clutch pedal assembly from the crew cab and it should swap in straight forward. The master cylinder.....I not sure if there's a marked hole on the u-haul or not. To use the auto in the u-haul you'll need a 4x4 tranny or are you planning to divorce mount a T-case? Or is it just a matter of changing the tail housing? I haven't messed with the auto's all that much. I just know it would be easier to make the u-haul 4x4 if you take everything off the crew cab. And by the way..... The army truck- I usually say that I "laid it over." It scared the hell out of me.
That BW is a fine case. I don't think it will be all that big a deal to swap all the 4x4 stuff. I basically did that on my truck.....kinda. It's not like your putting a square peg in a round hole here. It's ford stuff going back on a Ford. I still hate to see you part out the ole crew cab though.
Transmission cover floor panel swaps, no cutting, just more bolts.No way I would run the auto! I'm assuming I will have to cut a hole in the trans tunnel too. I have an NP205 sitting around but think I will stick with the borg-warner.