GMC SIERRA CK2 1999 Owner's Manual page 326

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. Replace the parking/turn signal lamp assembly and
tighten the screws.
6-44
3. Pull the bulb straight out
of the socket.
Fender Marker Lamps
(Dual Rear Wheel Pickup Models)
1. Remove the screws and
take the fender marker
assembly out of
the fender.
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