Hi, After I take top cover off of transmission this week (stuck rails?) I am moving on to the brakes! while underneath, I noticed that someone made an adapter plate and put a dual circuit Master cylinder that I recognize as a Mid 60's to late 80's Chev/GMC from years of selling auto parts. It is connected to 2 Hydrovac boosters, 1 going to the front,1 to the rear. I have never seen anything with 2 Hydrovacs before. The Master was frozen and only took 5-10 minutes to free up with a small hammer and a few squirts of WD-40. I actually have a half decent pedal. I am going to top off fluid and see what I get with the engine running. Is this an improvement over the single circuit like my Ford GTB? It even looks like the same 4572 Master that only has 1 Port. Some of the sites list the F-661 which I see has 2 Ports! Would that be 1 to Hydrovac, 1 to Brake Light switch? I already have all of the Wheel Cylinders and some of the hoses, getting more parts as I go along. I really don't know whether to go Part for Part or unbolt the Adapter plate go back to the Factory setup! I could use some input. Thanks. Russ Erwin.
