My 2 cents is spend your money on parts that will improve ride quality and reliability, new suspension bushings, Weber carburetor, new u joints, shocks, things of that sort....
Body lifts and slightly bigger tires aren't going to make your truck anymore capable then it already is. There isn't easily available options for front or rear lockers or taller gears to even push big tires.
If you are going to keep the drive-train mostly stock, then its best to just leave it alone, slap some 30x9.5 AT or MT tires and go have fun in the woods/desert/beach... wherever.