Have you looked into the inline 6 that GM is using in the current Trailblazer? I believe production started somewhere around 1998. It should fit physically into your truck, unlike a V8, and only comes coupled to an outo trans, your preference. I can't remember the specs on it, but the hp/tq is something like 250/275. These came out just after I sold my first tractor, a 55.1. I would have loved to drop one in. They are fuel injected, which adds some complication to the issue, but I believe well worth it in the end.
Devin
