Hey yall. I have been completely replaced the brakes in my 96 bronco with a 302 recently. i disk braked the rear and have 8 lug front outters. I removed the ABS and ran all new lines. I put in a new M/C and booster that go to a f350 of the same year. I put a proportioning valve on the rear brakes that are now disked, but it is currently set wide open. The problem i am having is that the brake pedal is very hard to push and it will stay down after i apply it. The motor also boggs down when i apply the brake. I have already replace the booster once and bled the brakes several times. Any ideas??