I have done a couple divorce t-case's. They work just as good if not better the a connected set up.If you blow the tranny you just drop it out, you dont have to drop them both!
Any way, I have a 85 shortbed I put the 400 tranny and a IHC t-case , the tranny is a short shaft 400 and has a slip yoke,and the u-joint bolt directly from the yoke to the t-case.I put it together for a test run to see if everyting worked and would last.That was 8 years ago and 50 thousand miles.Same u-joint and no problems,still going.
I did an 84 blazer the same way,It was a little tougher to get the t-case in the correct alignment for the u-joint.The frame is a litte different and had to make a lot different crossmember for it.But it worked ,the rear drive shaft was only about 30-35 inches long.
So do it !!
And also, both of thse rigs were one ton axles,454,400,IHC tcase,and 44 '' tires.