I promised several people on this forum that I would post results of the wheel swap on my 05 GT. I am happy to report that 04 Mach 1 (and 17" magnum 500 copies) will bolt right on with no interference and they still stay inside the fender lip. I have 2004 17x8's with 245/45/zr17 tires. Yes, the fender to tire gap increases slightly with the shorter tire(25.5" vs.26.5" stock), but I intend to lower my car approx. 1 inch, so the difference is slight. Next step is gears, any thoughts 3.73's or 4.10's?