Ok, I hooked my gauge light up to the light for the heater/fan controls above the radio. So the gauge lights will come on when I turn my headlights on. My question is this. On the back of the gauge, the terminal that says "to ignition switch".... where to I connect this to? Does this connect directly to the battery like my stereo amp is wired? Or do I connect it to an empty fuse terminal in the fuse box? I'm a little confused about the ignition wire, and the wire they say to connect to a 12v source that comes on with ignition only.