It's still awfully cold

[Libby]

Thanks for the info re: what the temp. sending unit actually does. The car doesn't overheat this time of year. I guess I shouldn't say she overheats in the summer; she does run hot, and sometime blows a little out of the overflow hose. As I've stated in a previous post, tho, she will overheat in the summer if a 180 thermostat is installed. (I've had this car, and driven her almost daily, since 1977, so I'm used to her little quirks) I'm also used to not having a lot of heat in the winter, but this is just not right.
My mechanic wants to remove & boil out the radiator (and the heater core again) once the weather gets a little warmer. When he replaced the plenum last week 2 of the original cables from the heater/defroster switch just fell apart, and he's got them temporarily rigged to work. He tells me that I also need the part that sits behind the switch plate that the cables connect to. (I'm probably describing this really badly, but hopefully someone will be able to decipher my meaning) Can anyone tell me what that part is called so I can order the right thing?
Sorry if this sounds as if it was written by a total doofus. I may not know much about cars, but I know what I like! Libby