Ever consider a "period correct" hot rod? Keep the truck basically original, but put in a hot 261 chev or one of the big jimmy sixes like they did in the 50s and 60's. My truck is a 1970 C/10 so it's kind of a different animal, but a period correct hot rod is what I would do with an AD, but hey, it's your truck you get to make all the decisions. They aren't always easy. In any case, welcome to the brotherhood of the busted knuckle where all true stovebolters and their trucks have been baptized by both blood and fire!
Boo Radley