GMC 2007 Envoy - Manual (Page 433)

4. Unclip the wiring harness (A) and remove the
three socket retaining screws (B).
5. Remove the socket plate.
6. Holding the socket, pull the bulb to release it
from the socket.
7. Push the new bulb into the socket until it
clicks.
8. Reinstall the socket plate and tighten the
three screws.
9. Reconnect the wiring harness.
10. Reinstall the taillamp assembly by lining up
the locator pins with the retainers in the body
of the vehicle.
11. Reinstall the two screws and tighten.
12. Close the liftgate.
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