1994 GMC Safari Owner's Manual - Page 32

To move it down, push in the adjuster at the arrows and pull down on the adjuster. After you move the adjuster to where you want it, try to move it up and down to make sure it islocked into place. You can move the adjuster up from a lower position by pushing upon it. just Adjust the height so that the shoulder portion of the belt is centered on your shoulder. The belt should be away from your face and neck but not falling off your shoulder.