Sounds like you're starting to hone in on a good direction. I've had boats in the past and always used a RWD truck to pull them out of the lake.
A great rear end alternative to for the S10 is an Explorer 8.8 rear end. They're really stout and they practically drop in short of a conversion U-joint. You can find these rear ends all day long at a Pick N Pull.
http://www.s10forum.com/forum/f13/ex...h-pics-513864/