I will be upgrading brakes on a m caliper equipped 911 soon. Currently I have 15" wheels w/ new sticky tires so I would like the brakes to fit the 15x7 wheels. Will 944t or boxter monoblock brake calipers fit? How difficult is this modification? I know that I will need new strut housings, but what about the rears? I would also consider '84-'89 carrera calipers as an option...not as sexy and maybe not as good. The car is mostly going to be a street car but will get use in Auto X and D.E. Engine has around 250hp if I had to guess. Bang for the Buck is a consideration.