Get the rear brakes off of a new F150 and install them. Should bolt right on. Might have to change the master cyl to compensate for the disc brakes on the rear. IF you truck has an 8.8 should be a direct fit.
SCT Tuner - 400.00
Jaws Racing Tunes - 150.00
Beating the wifes new GM truck - Priceless http://www.jawsracing.net/