First thing I would do is make that baby SWITCHABLE!
I dunno if Allen offers switchable programming but I do know that Bully Dog makes a great cat-back system and switchable programming that can get up to 150 extra hp out of that D-max.....its got a lot of potential. If it turns out you want something from Bully Dog, send me a PM and I will see if I can't cut you a better deal.

P.S. If you do go switchable, don't leave it in the extreme 150hp mode very long....it will burn that engine up.