[sacramentophil]

If you have the auto tranny, then Isuzu's 3.2/3.5 DOHC V-6 will bolt up to it. Depending on the model year, it'd have 190-250 HP and loads of low-end TQ.
Of course, bolting it up to the tranny is where the "easiness" ends. But, if one was inclined to swap out the stock engine for anything else, this may be one of the cheapest/easiest to find.