I have a '75 Mercury 650 that I recently purchased and replaced the impeller. I put the engine in forward before removing the lower end, but when putting the lower end back on I shifted it into neutral to get the lower end to slide all the way up. Now neutral is forward. How to I get this solved now? I have dropped the lower numerous times and tried different forward to reverse to neutral combinations but it seems to just be stuck in forward, now I have no idea what is going on.