from the dash there is a gray 12v radio switched wire and a green illuminatoin wire but from my jvc cdplayer radio there is only a battery wire, aground wire and a red accessory wire. would i connect the gray and green wires from the dash to the red wire from the radioor if not where exactly would i connect those wires to? that would be for a 1990 toyota corrolla. also is there a way to check a radio to see if it works correctly before installing it in the car? how would you go about doing that?