GMC Yukon 2007 Owner's Manual page 507

To replace one of these bulbs, do the following:
1. Open the liftgate. See Power Liftgate on
page 132 for more information.
3. Pull the taillamp assembly rearward until you
disengage the inner pins on the taillamp
assembly from the vehicle.
2. Remove the two
screws from the
taillamp assembly.
4. Press the release tab, if bulb socket has one,
and turn the bulb socket counterclockwise to
remove it from the taillamp assembly.
5. Pull the old bulb straight out from the bulb
socket.
6. Press a new bulb into the bulb socket and
insert it into the taillamp assembly. Turn the
bulb socket clockwise into the taillamp
assembly until it clicks.
7. Reinstall the taillamp assembly. When
reinstalling, make sure to line up the pins on
the taillamp assembly with the vehicle. If
you do not do this, you will not be able
correctly install the taillamp assembly.
507