WARNING: This page is about a different car, the 2010 Pontiac G5 and 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Removing & Installing Control Valve Body Assembly
Courtesy of GENERAL MOTORS CORP.
Remove the remaining twelve bolts (9, 12 and 16) from the control valve body assembly (18).