I see you're looking to put a D44 in the back, but have you considered an AMC 20? If you find the right one, they're really desireable if you can find the right one. There are certain versions which have given all of them bad names, with two piece axles and wimpy axle tubes. BUT, ours had thicker axle tubes than normal ones, and one piece axles which seem thicker than D44's. The ring and pinion have a lot more beef than a D44, that's for sure. I think H1's use amc 20 center sections too. D44's are fine for front ends, I just like to have a beefy rear end.
Looking pretty good though. So that that stock crossmember wasn't in your way? Our diff was hitting it with over 12" of lift, I guess maybe it was just a lot farther forward.