Brake Rotor Size Upgrade

A popular low budget mod is to upgrade your 3.7L mustangs brakes to the larger 2011-12 Mustang GT brakes.
Roush performance sells these 2011-12 GT brakes take off systems on ebay, and their website. For $125 you get calipers, brackets and rotors.

The rotor is a 13.2 in versus the 12.4 inch rotor from the 2011-2014 3.7L V6.

I measured the caliper piston size to make sure they were the same. The part numbers a different.
Here is the 2012 GT Caliper – BR33-2B119-DA
Here is the 2010 GT Caliper – BR33-2B119-AE
Here you can see the caliper bracket size change. You can order them directly from Ford as well.
Here is the 12.4 bracket. VFSU 0055-0 6
Here is the 13.2 bracket. VFSU 0162-0 1
Now you can pull your caliper off. Have a jack stand handy as to not let the caliper hang from the brake fluid line. The pull your pads and bracket.
This is a good time to grease your bracket. Clean the rotor with brake cleaner and then place it on the hub. Then put your new bracket on and then your brake pads.
If your caliper does not slide on then you need to compress your pistons a little. Be sure to use a solid flat surface to press them in.
Put your caliper back on and then be sure to bed in your brake pads. Get out on the highway and take an exit ramp when its clear and brake firmly from 60 mpg increasing brake pressure quickly unit you get to 10 mph and then repeat 8-10 times. Try not to stop if at all possible.