I sold the 2005 GT and still have the wheels and tires from it. They are the Konig Beyond's, 20x9 front and 20x10 rear with Nitto NT555 at 255/35-20 front and 275/35-20 rear. They were on the car for 100 miles and still look brand new. Professionally mounted and balanced.
I am looking to get $1600 for them. They are located in the Orlando, FL area and prefer a local pick-up. Delivery within a reasonable area is also feasible or meet somewhere. Otherwise shipping will be added.
I also have a brand new set of Eibach lowering springs, still in the box, for $200 + shipping.