So my buddy ZombieSlayer upgraded his sixer to the Brembos. (You can't hide money!) Anyway, he had the Performance Pack brakes which are the same as the GTs. A few emails and a FedEx truck later, my sixer has changed from the factory base front brakes to the larger PP brakes. All you need to do this are the front brake brackets themselves (They run about a 100) and the larger rotors The PP brakes are 13 1/8 " and the regular V6 brakes are 12 1/2" in diameter. Easy install about 25 mins per wheel (not including caliper paint time. Here are a few pics of the differences. Quite a change in wheel gap between the caliper and the rim. That's no joke that you can't do this unless you have at least 18" rims.