For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningCruise Control
For vehicles with cruise control:
: Press to turn the cruise control system on and off.
RES/+: Move the thumbwheel up to resume a previously set speed or to accelerate.
SET/−: Move the thumbwheel down to set a speed or to make the vehicle decelerate.
: Press to disengage cruise contro ...
Rear Bumper Fascia Outer Guide Replacement
Preliminary Procedure
Remove the rear bumper fascia. Refer to Rear Bumper Fascia Replacement.
Rear Bumper Fascia Outer Guide Rivet (Qty: 3)
Special Tools
BO-594-A Hand Rivet Tongs
For equivalent regional tools, refer to Special Tools.
Rear Bumper Fascia Outer Guide
...
Installation Procedure
Align the body side outer panel reinforcement.
Clean and prepare the attaching surfaces for welding.
Position the body side outer panel
reinforcement on the vehicle.
Verify the fit of the body side outer panel reinforcement.
Clamp the body side outer panel reinforcement ...