Success! yeah I saw that once & it was from not setting the cap straight down. Good possibility your diagrams would help even tho they are a year or so later. There is a vacuum valve on one of the heater hoses between firewall and eng. Mine was leaking so I just replaced it with a regular on/off shutoff valve with a hose barb on each end & I open it in cold weather & shut it in warm/hot weather so the AC will be right when I need it. Works perfect! I do wanna trade the truck for a 63-66 2dr A body daily driver with good floors/sheetmetal/glass & drivetrain can need work. A guy I built an eng for bought it from the original owner & when my 65 dart was Tboned he sold it to me so I would have something to drive. it is all oiginal (ex for that valve & tune up items/fuel pump & has never been hit. Holler when you can