GMC 1999 Suburban Owner's Manual page 317

Composite Headlamps
1. Remove the two hex head pins at the top of the
radiator support, as shown.
2. Pull the headlamp lens assembly out.
4. Turn the bulb counterclockwise and remove it.
5. Put the new bulb into the lens assembly and turn it
clockwise until it is tight.
6. Plug in the electrical connector.
7. Put the headlamp lens assembly back into the
vehicle. Install and tighten the two hex head pins.
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3. Unplug the
electrical connector.
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