speckle, why can't you pull the drive shaft? Is it literally stuck? If so there could be some rust holding it in the power head unit. There is suppose to be a seal to keep water intrusion from reaching there, but sometimes it gets trashed and water goes there and rusts it up really bad. So it may take a lot of force to get it apart. And if you do get it apart, clean both the drive shaft splines and the power head splines perfectly clean and then apply grease ONLY to the sides of the drive shaft splines when reassembling it again. DON'T put any grease on the end of the drive shaft. It will create a seal and not allow the drive shaft to fit properly. But make sure you install a new seal or "O" ring to help keep water out... JMHO!