I have an older Glastron boat with a Mercury 1000 (100hp) engine. The engine has an brass prop on it. I need to remove the lower unit and replace the seals (will not hold any dope in the foot, all leaks out) I can not get the prop off. It has the one nut with the lock washer, all of that came off fine. The shaft is the spline type, but the prop will not slide off. I have taken a rubber hammer to it VERY HARD and nothing. I have sprayed it with penatrating oil and let it sit for days while spraying it. IT WILL NOT COME OFF. Does anyone have any ideas???? Please Help!!