Fix for a 4-button climate switch

Hi, new forum member here:)

Anyways, this is the exact information i was looking for. I have a related question you may have the answer to.

I have a 1960 dart that has the 4 button controller. I have vachum to the controller but the buttons don't seem to want to move. Should they be stiff or does the vachum help them move in and out or do i need to lubricate this unit somehow.

As well my wiring is a little messed up as I have no power to the controller right now so the fan is not running. I doubt this has any bearing on the controller push buttons being very stiff but i have been wrong before. Could this condition be what you are referring to as melted by the blower on high?