GMC 1998 Savana Van Owner's Manual page 273

Headlamps
You have either a sealed beam headlamp system or a
composite system.
Sealed Beam Headlamps
2. Unplug the lamp assembly from the connector.
3. Install a new headlamp.
4. Reverse the previous steps to reinstall the headlamp.
1. Remove the four screws from the headlamp retainer.
Pull the retainer out and set it aside.
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