Hunts, Tony, Cletis and ol pal Korn. Thanks for the good advice on brakes. I need an education on proportioning and residual pressure valves. What are they and what do they do? My donor IFS and rear axle are out of an 84 GMC half ton. The front end came with the power steering box and the dual master cylinder. The booster was missing. There is what appears to be a proportioning valve there also. Can I use any of this stuff over? Cletis thanks for the pics. I have all the popular catalogs except CCP. Pop E-mail about CCP. Thanks to all .