Chevrolet 1999 Express Van Owner's Manual page 269

Headlamps
You have either a sealed beam headlamp or a
composite system.
Sealed Beam Headlamp
1. Remove the four screws from the headlamp retainer.
Pull the retainer out and set it aside.
2. Unplug the lamp assembly from the connector.
3. Install a new headlamp.
4. Reverse the previous steps to reinstall the headlamp.
Composite Headlamps
1. Open the hood.
2. Locate the rear side of each of the headlamps.
3. Without removing the headlamp assembly itself,
remove the bulb assembly from the back of the
headlamp on the driver's side by turning the bulb
counterclockwise one quarter of a turn.
4. On the passenger's side, turn the bulb clockwise one
quarter of a turn. Also, to remove the bulb on the
passenger's side, you will need to move the battery.
yellowblue
6-33