the tapered gear at the bottom of the steering shaft has stripped. I have ordered and received replacement part. I have removed the hood and sides. I have also removed the deck for easy access. I have removed the gas tank and the bracket it sits on. I now have easy acces to the steering shaft. The phillips head screw on the bottom won't budge, and I'm afraid to strip out the head of the screw if I try too hard. Any suggestions?