hey jared, i'm not a member of any diesel forums so i figured i'd just ask this here, lol. my dad has an 07 duramax (LBZ) 4x4. he wants to make some more power out of it. the truck already has a K&N FIPK installed and he just put larger 33" tires on it. he's looking at getting a bigger exhaust system for it, and a hand held tuner, but we can't decide on which setup would be best for him? should he just buy a catback, or is it worth it to do the entire turbo back system with no cat? also, he wants a programmer that is fairly easy to use and that will not only calibrate his speedo for his larger tires, but also give him some decent power gains. what would you recommend? any input is helpful :beer: