Chevrolet 1998 Express Van Owner's Manual page 275

3. Squeeze the tab on the side of the bulb assembly
while turning it to the left. Remove the bulb
assembly from the back of the lens and replace
the bulb.
Reverse Steps 2 and 3 to replace the bulb. Turn
the socket to the right to replace it in the lens
assembly. Replace the screws on the parking/turn
signal lamp assembly.
Sidemarker Lamps
1. Remove the screw from the top of the lens.
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