I have these on my 2014gt, but they will also fit gt500 also please click link for full details.
http://www.svtperformance.com/forums/showthread.php?1066594-Willwood-superlite-4r-big-brake-kit
http://www.svtperformance.com/forums/showthread.php?1066594-Willwood-superlite-4r-big-brake-kit