1997 GMC Sonoma Owner's Manual - Page 280

Windshield Wiper Blade Replacement See "Normal Maintenance Replacement Parts" in the Index for the proper type of replacement blade. I NOTICE: I Use care when removing installing a blade or assembly. Accidental bumping can cause the arm to fall back and strike the windshield. 1. To remove the old wiper blades, lift the wiper arm until it locks into a vertical position. A. Blade Assembly B. Arm Assembly C. Locking Tab D. Blade Pivot E. Hook Slot E Arm Hook 6-42