How does the AC temperature switch work?
 

I'm thinking about using my AC temp switch as a kill device to the fuel pump since I no longer have AC....I presume its a reostat of some kind but its not obvious? I can probably just replace the back with any on/off switch going the relay but leave the front intact as the old AC temp?

Also, I tried to remove it but dont see how to take the front off? Ideas?

Thanks.