GMC R2500 Wiring Harnesses & Electrical - OEM-Fit Harnesses & Components

Restore your GMC R2500’s electrical system with precision-engineered wiring harnesses and electrical components designed specifically for your vehicle. Each harness is manufactured to match the original routing, connectors, and circuits of your GMC R2500—restoring the wiring behind the dash, under the hood, and through the body to factory-correct, or factory-improved, condition.

Our GMC R2500 electrical lineup includes complete wiring harness sets, battery cables and ground straps, switches, electrical devices, and update/conversion products such as alternator upgrades and electronic ignition conversions. Every component is manufactured and tested to deliver dependable, factory-correct performance, and is organized by your vehicle’s exact year to ensure the harness or component you order is the one built for your GMC R2500—not a close approximation.

Use the Vehicle Selector above to find the correct wiring or electrical component for your GMC R2500, or browse below to explore available options. Whether you’re chasing judging points with a numbers-matching restoration or simply getting your GMC R2500 running right, Factory Interiors makes it easy to restore your electrical system with wiring products proudly made in the USA.

1973-1978 GMC R2500 Air Conditioning Low Pressure Cut-Off Switch

-O.E.M. replacement-, located on liquid line,

1976-1978 GMC R2500 Air Conditioning Thermostatic Switch

-O.E.M. replacement-, mounts to evaporator near receiver/accumulator

1973-1980 GMC R2500 Backup Light Switch

-O.E.M.-, 4 speed manual trans.

1981-1987 GMC R2500 Backup Light Switch

-O.E.M.-, 4 speed manual trans.

1988-1989 GMC R2500 Backup Light Switch

1988-1989 GMC R2500 Backup Light Switch, built to original specification.

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(76 Total Products)