The trick turbo kit works for 4wds too. A guy put down a hair over 500rwhp in a 4wd 5.3 with just an LS6 cam and I belive 8 or 9#s of boost. I would throw the 6.0 in there with a cam and run that for a while and save for the turbo kit. Ranwalk on PT put down 545rwhp(or something close to that) with a whippled 6.0 and cam but he is 2wd.