When you take out the heater and a/c controls, there are the vacuum lines that are coming from the back of it. Some that are clustered together, and then one that is by itself. Does anyone know where the one that is by itself hooks up to? My vents on my dash, and floor havent worked since its been disconected. Only the defrost vents work. My Haynes manual doesn't show where they all come from, only shows them on the back of the heater controls. Anyone help?