GMC 1996 Sonoma Owner's Manual page 258

Headlamps
Sealed Beam Lamps
1. Remove the screws from
the headlamp retainer.
2. Pull the headlamp out
and remove the retainer.
..
. .
3. Unplug and remove the headlamp.
4. Plug in the new headlamp and put it in place.
5. Put the retainer on the headlamp and install and
tighten the screws.
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