Here is the part number that Troyer has listed.

"This kit requires a 1 inch shorter serpentine belt, and we recommend the Goodyear Gatorback serpentine belt as it's much higher quality, and are no more expensive than the factory belt. This will also stop the serpentine belt "squeal" that is heard many times during heavy-throttle upshifts in these vehicles, especially if a performance tune is being used. We carry these Goodyear Gatorback belts, for 2002 & 2003 F-150's, order our Part# 4060980, and for 2004 & up F-150's with the new 3-valve 5.4 engine, order Part# 4061010. All of these belts are listed at the bottom of this page, as well as in the "Belts" section of our Store here. For 2003 F-250 SuperDuty Trucks, the correct belt to order is our Part# 406990. "

It is their part number but they have it listed as 1" shorter. I am sure the guys at the parts counters could pull that out.

Here's the interesting thing the kit Dixie got was still able to use the stock length belt. The shorter one he ordered didn't fit. His was from summit and for the 4.6L.
So to this day I'm still scratching my head on that one?

Lars

Yeah, I scratched my head at that too; they list that theirs uses the original size belt.

Yup, still running the stock length belt. I know my RPMs dropped once the kit was installed so it did what it promised. Now if I could only find the time to install my efans!