I built mine in place of the cigarette lighter since it didnt work anyway. People always freaked out when they found out that was a **** and it controlled the sub.
I just got a washer painted it black and stuck it in the hole, then I made a plate out of some very thin sheet metal as a place for the switch to mount. I made the sheet metal so that it mounted to one of the screws that held the 4wd switch on and glued it in another spot. You can just mount the **** in the washer but it isnt quiet flush so you can see the nut that held it on, at least with mine. sry for the blurry pics
Ohh and you have to take the **** out of the factory casing or it wont fit.