hi there i reciently fitted a new water pump kit onto my lower unit on my 65hp mercury 2 stroke outboard and i have taken off the lower unit lots of times and refitted it and it was fairly easy but when i tried it now it wont go on atall and its nothing to do with th water pump because that doesnt touch any thing its only the splins on the drivshaft that wont line up inside and iv tried moving the flywheel at the same time as trying to put it in but it makes no difference its never been this hard and its in reverse gear on the outboard as well as the controls and thats how it always goes on so i dont know what it could be also i have looked inside the outboard and the place where the driveshaft fits in is fine and moves when turning the flywheel please help .