Soon it will be time to have the 1957 Power-guild re-built in my Nomad. I once read in an article in Hemmings classic car magazine about making sure that it has the vent breather , and then I read somewhere that if you install a back flow valve in the correct one of the two transmission lines it won't constantly pee transmission oil into your catch pan, or all over your garage floor. Be sure to wear a welder's glove ever time you check the transmission on these cars or it will burn your arm off. Not fun . If anyone knows about this back flow valve please help . Domenic