The last guy to own that car must not have had a good idea of what he was doing. All you need to do is take a simple flip open fuse box, or even in line fuse, hook it to one of your 12V sources, and wire in a toggle switch :-D but make sure before playing with wires to always disconnect the neg. battery cable! (I've taken many hits from batterieswhile installing/swapping amps and installing PA systems). If you thought you were really cool, you could buy a capacitor and wire everything to that = no dimming of lights at night! *and still use a toggle switch for things you don't want on all the timewhile the car is on such as neons*