Toyota: '86 Van heater control broken

Just bought this and it has only a few obvious problems. The front
heater control is broken--the lever that influences hot/cold. This
works two cables--a mix door (I think) and a water valve. I suppose
it's broken because the valve stiffened up and the lever was forced.

Is this common?
How does one get the control out of the panel?
Suggestions on repair?

Thanks.

am