Hi Doug and welcome, the 4x4 has the desirable LSD (limited slip diff) and bolt on drive shafts.
The 4x4 front hubs can't be used because they have a drive shaft which will be removed, the enging is large and heavy and for its size dosen't offer much power. I had a 4x4 and after alot of work didn't use any of it because mine was rusted to hell and the half shafts bolts would not come off, I came across a standard RWD sierra and used most of it. Sold the 4x4 for scrap and made £30 more than I paid though
This forum is great for advice and help and you can always rely on an answer to most questions by searching old posts.
Hope that helps, hopefully someone will jump in and recommend using the V6 as there are a couple of builders who have used it.