BROTHERS Trucks is proud to offer American Auto Wire's high-quality wiring harnesses. Factory Fit engine harnesses are manufactured according to the original General Motors specifications. Each part number is fully assembled, taped, and ready to install upon arrival. This harness will plug into the firewall in the original location and will follow the original routing in the engine compartment. A combination of the engine and front light harness accomplishes most functions under the hood of an early GM vehicle. This harness is built for an original alternator with an external voltage regulator. Front light harness design can change significantly from year to year, but most harnesses include circuits for the charging system, park and turn indicators, headlights, horn, and horn relay.