I just finished the ignition switch replacement. I read and reread the instructions posted and everything went smoothly until it came time to put the key cylinder back in. It wouldn't go so I took a screwdriver and rotated the white plastic piece inside the opening to match the cylinder. It finally went in and the car even started. I turned it off and removed the key and headed for a deserving beverage. I tried to start it again and the key will not budge in either direction. 2000 pontiac gp with a delphi 3 system. Any ideas???