1/2 to 3/4 ton driveshaft

[GreenMystChevy]

What driveshaft should I use beinig that my transfer case has the small u-joints yet the axles have the larger ones. I can't use my existing driveshaft unless I use hybrid u-joints. I thought that 3/4 tons had something like a 4" diameter shaft. Is this better and will it last longer?

I am putting together my '72 and I have put '75 3/4 ton axles under it. I made sure to have 3/4 ton axles under there because I am going to be running 38"s and maybe bigger later on and I don't want to be replacing things all that often, including u-joints snapping. I am running a Rockwell 221 transfer case.

What is going to be my most efficient way to go as far as quality and price? Completely new shaft custom made, different end yolk on my existing shaft to accept the 3/4 ton u-joint, different bottom shaft (the longer driveshaft that slips onto the little one bolted to the transfer case), etc. Thanks guys.