Removal of the wiper arms requires the use of a special tool, G.M. J-8966, or the equivalent. Versions of this tool are generally available in auto parts stores.
Insert the tool under the wiper arm and lever the arm off the shaft.
Detach the washer hose from the arm.
Remove the arm. Installation is the reverse. The proper park position for the arms is with the blades approximately 2 inches (50 mm) above the lower molding of the windshield. Be sure the motor is in the park position before installing the arms.