GMC 1999 Sierra 1500 Pickup Owner's Manual page 341

6. Replace the bulb retainer.
7. Replace the rear light assembly and tighten the screws.
8.
Close the tailgate.
Sear Lights, Chassis Cab Models
U
1. Using your hands, peel the rubber seal away from the lens.
I
PO497
2. Lift the lens off the light assembly.
3. Slide the socket out
of
the light assembly
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