Bigtonka,
The switch for my '48 truck (like Brad showed us) is 6 volt but I used a resistor to drop the 12 volt coming in and also on my 6 volt heater motor.
The switch has 3 speeds Hi, Med, Lo and off.
I have mine mounted to the left of the steering wheel next to the column there are 2 holes to mount the switch in under the dash, next to the defrost/heat vent pull .
Hope this helps!
Mike
