77 280z The heater valve on this car has been in a permently open position, I thought it was corroded into that position but I have cleaned it, removed a bunch of silicone gasket pieces but still can't get it to close. When I look at it close up I'm thinking I might be missing a part that connects to the plunger valve or perhaps the rubber seal/diaphragm is so hard with age that it can't move. In the first 2 pics I have removed the switch that sits on top of the plunger, you can see th