GMC Sierra 2000 Owner's Manual page 315

Front Sidemarker Lamps
(Composite Headlamps)
2. Reach through the opening and turn the sidemarker
bulb socket counterclockwise and remove it.
1. Remove the four
screws and pull out the
parking/turn signal
lamp assembly.
4. Put a new bulb into the socket and push it in until
it is tight.
5. Put the socket back into the sidemarker assembly
and turn it clockwise to tighten it.
6. Reinstall the parking/turn signal lamp assembly and
tighten the screws.
3. Pull the bulb straight out
of the socket.
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