The rear outboard head restraints can be removed if they interfere with the proper installation of the child restraint.
To remove the head restraint:

Warning
With head restraints that are not installed and adjusted properly, there is a greater chance that occupants will suffer a neck/ spinal injury in a crash. Do not drive until the head restraints for all occupants are installed and adjusted properly.
To reinstall the head restraint:

If necessary, press the height adjustment release button to further lower the head restraint.
See Head Restraints on page 3-2.
Securing a Child Restraint Designed for the LATCH System
Replacing LATCH System Parts After a CrashWindshield Wiper/Washer
The windshield wiper/washer lever is on the right side of the steering column.
Move the lever to one of the following positions: HI: Use for fast wipes.
LO: Use for slow wipes.
INT (Intermittent Wipes): Move the lever up to INT for intermittent wipes, then
turn the INT band up for more ...
Service Publications Ordering Information
Service Manuals
Service Manuals have the diagnosis and repair information on the engines, transmission,
axle, suspension, brakes, electrical, steering, body, etc.
Service Bulletins
Service Bulletins give additional technical service information needed to knowledgeably
service General Motors c ...
Accessories and Modifications
Adding non-dealer accessories or making modifications to the vehicle can affect
vehicle performance and safety, including such things as airbags, braking, stability,
ride and handling, emissions systems, aerodynamics, durability, and electronic systems
like antilock brakes, traction control, a ...