1990 GMC R3500 Electrical, Lighting and Wiring Parts

Check out this headlight wiring and taillight wiring diagram.

Read how to wire a lightning sprint engine. This detailed account of how to successfully wire an engine will ensure a smooth installation.

Learn how to install spark plug wire terminal ends. Our step by step guide takes you through terminal end and boot installation with the use of a wire crimping tool.

Watch our Steering Column Wiring Guide video for useful tips on wiring your new steering column for your vehicle. Ididit takes you through the wiring process.

In this Tech Tip, a returning customer asks for advice on wiring harnesses for his ’29 Ford roadster project.

Learn how to install 1970-73 RS Camaro reproduction parking lamps and how to overcome some obstacles during the installation.

Are your gauges reading erratically or does your car run out of power at high rpm? It may be the cause of a bad ground. Speedway Motors can show you how to diagnose and fix the problem in no time at all!

In this budget build, a GM rear end is upgraded in order to hold 400+ HP. See how spherical bushings are replaced in a used 8.5” GM 10 bolt rear end.

Read how to install rear drop spring to lower a 1969 C10 pickup. Follow these steps for a smooth installation.