Not satisfied with the harness previously available, we designed our own with the intention of producing a high quality harness with instructions that anyone can follow! We believe this is the best available. A complete quality harness to replace original perfectly. Uses modern PVC coated copper wiring in the correct color codes. Complete with detailed installation instructions. The end of each number is tagged with a number which correspondes to a list of wires. Simply follow the list, installing the correct numbered wire to the location specified. Generator harness for use with the original charging system. Will work on GMC with modification to the instrument cluster wiring and with the GMC engine wiring.