GMC 2006 Sierra - Manual (Page 479)

Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp
To replace one of these bulbs, do the following:
1. Remove the screws and lift off the lamp assembly.
A. Cargo Lamp
B. Center High-Mounted Stoplamp Bulb
2. Remove the back plate from the assembly by
pressing the release tabs.
3. Remove the CHMSL bulb by pulling the bulb
straight out from the holder back plate.
Remove a cargo bulb by turning the socket
counterclockwise and pulling the bulb straight out.
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