climate lack-of-control system, 1984 300D

[Jerry_W]

I have been trying to get some modicum of control from my climate control system.
I have outer dash vents and defrost vent HEAT under all conditions (except off), the fan seems to have a mind of its own, and the heat is being pushed into the car even when the AC compressor is engaged (and there is a temperature differential between the high side and low side hoses). Mitivac shows no leak at the green supply hose, but I can't seem to get the system to open the #1 vacuum solenoid and check for leaks downstream.
The diagram from the CD manual I have (supposed to be the FSM) seems to show vacuum lines being connected to the pushbutton switch unit, so no help there. It does tell me what position everything is supposed to be in when working correctly, but if it was working, I probably would not be in the manual!
FYI, all that is left the foam hose to the dash sensor is a gob of goo.
Where do I go from here?