"I have a 1977 25 HP long shaft Evinrude needing lower unit repair. I can not remove the unit as the long stud at the rear will not break free. I have tried heat, cold, WD 40, and 2 lock nuts to turn the stud. The gear case and extension move slightly at the front. The stud seems locked in all 3 components. Any suggestions. I'm afraid I will break one of the castings. Bill"