A few hours south of you are two highly qualified techs for performing the axle bolt upgrade and any other maintenance the 05-06 GT's require. Jason Heffner's shop in Sarasota and Sarasota Ford (Rick Weigewroth, tech) are both experienced in all manner of GT upgrades.
I think 2007 was too early for the second, correct, Ford fix. Others will chime in to identify the clues as to whether you have the first (incorrect) fix or the proper second.
Although I didn't make the cut for a NFGT I've enjoyed all of your experiences vicariously. I still can't believe my good fortune to own my '06 Tungsten. 45,000 miles and I ain't sell'n to no one!