Was it Bill Franco?
He came out and changed a bunch of parts, trans, shaft, diff, etc. That didn't work so I dialed out the vibe with a couple of hose clamps around the driveshaft. Worked on both the '99 and '01.
I checked out a GT500 while I was getting a new battery put in the car today. Maybe I'm getting old (I am!), but for $44,000+ I'd much rather have something like a BMW 335. The GT500 struck me as a warmed over body style with very few comfort/convenience options. The engine is a rush, but that gets old quick without the other pieces. Probably why I put so few miles on the Cobra. It's too bad Ford doesn't package a tarted-up version of the Mustang that has all the modern bells and whistles.
Jeff