Replace the Third Brake Light on 2000 GMC Sierra - Morsun Technology

To access the third brake light, you need to remove the two exterior screws located on the top of the cab, directly above the rear window. Use a Torx driver (usually T15 or T20) to remove these screws. Once the screws are out, the housing may feel stuck due to the old, deteriorated foam gasket acting like glue. Do not use a screwdriver to pry it off, as this will damage the paint. Instead, gently rock the housing side-to-side or use a plastic trim tool to break the seal. Lift the assembly out and disconnect the wiring harness by pressing the tab.
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