GMC 1996 Sierra Owner's Manual page 290

Front Turn Signal Lamps
(Sealed Beam Headlamps)
1. Remove the two screws
at the inside edge of
the parkinghrn signal
lamp assembly.
2. Remove the lamp assembly by swinging
it
out from
the
inside edge and sliding it out at the outside edge.
3. Squeeze the tab on the side of the lamp socket while
turning the socket counterclockwise.
4. Pull the socket out of the
lamp assembly.
5. Push in gently
on
the bulb, turn
it
counterclockwise
and remove
it
from the socket.
6. Put the new bulb in the socket, gently press
in on the
bulb and turn
it
to the right until it is tight.
7. Put the socket back into the lamp assembly and turn
it
to the right until
it
locks.
8. Put the parking/tut-n signal lamp assembly back into
the vehicle and tighten the screws.
6-40