D&DC

Recently we picked up a low mileage triple black 2004 Mustang GT Anniversary Convertible. We've made a couple of minor mods, but the thing that bugs me the most is how the stock wheels sit in so much, particularly on the rear.

Can anyone suggest a proper wheel and tire size combination that will give the GT a more aggressive stance and wider tread without incurring clearance problems on the rear fenders?

Thanks.