I have a mid '70's model merc 115 inline 6, great running motor... when it's running. My problem right now is I have had the gearbox apart, re-assembled and my gears are backwards. I'm new to this site but I have found a wealth of useful info already. Can anyone tell me how to put this thing back together the right way? I'm guessing the cam on the bottom of the shift shaft is out of position, where should it be when I re-install the gear assembly, neutral, forward? 