I've got a 73 Cuda that I have had since I was a teenager. I made it into a nice ride and then life got in the way and she went into storage. Fast forward 30 years and I'm finally getting around to working on it again. My present project is the brakes. I have basically replaced or rebuilt the entire front disc/rear drum stock setup. New master cylinder, lines, hoses, calipers, discs, etc. My problem is that I cannot get any fluid to the rear wheels. When I put the new lines on, I pulled the stock proportioning valve apart and cleaned/inspected it. All the o-rings, gaskets, etc. were in good shape so I did not replace them. Even with the rear line removed, I can't even get a drip while pressing the brake pedal. If I loosen the lines from the mc to the proportioning valve, they will leak, so I'm getting pressure from the mc. I suspect the proportioning valve is bad? Did I miss something when I was in there? Searched the internet and can't find a stock replacement. I found this one on ebay-http://www.ebay.com/itm/390486260576?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT Has anyone used one of these with success or failure? I know about the Wilwood adjustable but would like to remain as close to stock as possible for now. Thanks for any help or suggestions.