Well I have been running my 03 with 99,000 miles on, loaded with the Diablo Extreme tune for about a month now. I've read that 2 weeks of that can take care of the clutch in a hurry, now to speed up the process I installed 75hp injectors, and still no slipping, but I'm sure it's coming. Just wondering which clutch to go with, a 550 hp single disc? Or dual disc? Then for the Nv4500 do I have to change the input shaft to be able to change to an aftermarket clutch, I could really find info regarding the 4500 for a 3rd gen so any help would be great!