Can anyone help me with how the heater/vent/def controls are supposed to work? When I got my 40 the lever had the pointed part faced towards the back and never switched everything right. I looked up some pictures online and it appeared that mine was on backwards, as they showed the pointed side towards the front. I flipped it around (as the pic shows now) and it still isn't working right. The actual levers move freely and aren't frozen up or anything. Also, some of the pics I found online didn't have the middle slot that controls the bottom vent flap. I'm guessing the bottom flap closes off when you select defrost? Any help with how this is supposed to look and work would be much appreciated. Mine is a '75 model by the way if that helps with a solution.