How Are Wires And Resistor Connected To Console Gauges In Apr 12, 2012How Are Wires And Resistor Connected To Console Gauges In Camaro? Customer Question. the black wire is a ground. As far as how the gauges hook up, the factory wiring harness simply plugs into the back of the factory gauge. The fuel gauge uses a tan wire from the sending unit. Temp gauge uses green from the sending unit. I have a 99 Classic Update Kit - 1969-72 Chevy Truck We Make Wiring Complete Wiring Kit - 1969-72 Truck For. Chevrolet Truck 1969 Chevrolet Truck 1970 Chevrolet Truck 1971 Chevrolet Truck 1972 Kit Features: Replacement headlight switch with internal 30amp circuit breaker included. Retention collar nut, adjustable length shaft, and custom knob are also included.