Reading up on having a spare tire instead on the inflator kit. Other than GT500 wheel this one look like an option? Spokes are arched out enough that looks like it would clear the brakes.
http://www.ebay.com/itm/FORD-MUSTANG-GT-COYOTE-18-SPARE-WHEEL-TIRE-05-06-07-08-09-2010-2011-2012-2013-/281888688946?hash=item41a1e00b32:gYQAAOSwHPlWc3sj&vxp=mtr
http://www.ebay.com/itm/FORD-MUSTANG-GT-COYOTE-18-SPARE-WHEEL-TIRE-05-06-07-08-09-2010-2011-2012-2013-/281888688946?hash=item41a1e00b32:gYQAAOSwHPlWc3sj&vxp=mtr