I have some info for anyone who has a 2000 chevy silverado three door with a plow package and wants to hook up a signal light to the existing aux. light switch on the dash ( next to the airbag switch). The switch is pre wired from the factory. All you need to do is install a fuse (under the hood in the fuse box). The feed coming from the switch goes to a relay directly behind the drivers seat under the plastic molding. Email if you need any more info.