2008 Chevrolet Silverado 1500 | Stereo Wiring Diagram 2008 Chevrolet Silverado 1500. March 31st, 2012 Posted in Chevrolet Silverado. 2008 Chevrolet Silverado 1500 Stereo Wiring Information. Radio Battery Constant 12v+ Wire: Orange. Radio Ground Wire: Black/White. Radio Illumination Wire: Gray. Stereo Dimmer Wire: Brown. Stereo Antenna Trigger Wire 2008 Chevy Silverado Radio Wiring Diagram | Free Wiring Assortment of 2008 chevy silverado radio wiring diagram. A wiring diagram is a streamlined standard photographic representation of an electrical circuit. It reveals the elements of the circuit as streamlined shapes, and the power as well as signal links in between the devices.