I've subscribed to this thread because I have the same issue with my Focus ST. In place of the Focus, I was going to by a new GT 500, but didn't want to risk adding a driveshaft discount. A Mustang can't be towed 4 down. How did you adapt your Mustang to keep the rear tires on the ground?
Fran, Mary & Zoey (silver Cocker)
2006 Itasca Sunrise 35A, 2005 W-22, Allison 1000 5 speed
'13 Ford Focus ST or '10 Prius on Master Tow Dolly 80THD-SB or '00 Jeep Cherokee 4-down