I considered a '72 4 x 4 (still could do it as I have the parts). The Blazer frame would need to be stretched (11" wheelbase as I recall, perhaps a bit at the back). I picked up a Blazer frame at a show from one of those "buy a new kit, break it up, sell the parts" guys. Later I got another Blazer minus the top but otherwise complete. I was going to (still might) cut the inner fenders from the Blazer for the pickup, and stretch the frame by using two frames cut in half off-center. The Blazer interior floor and side panels could be used to build a new interior for the pickup, to get rid of the one-piece bucket.
--Mark