"I have a 1991 mercury 90 # cylinder,just put all new seals in lower unit with new water pump.I put the lower unit back in thinking it was right,I took my Wife daughter and Grandparents out today for the first time since I did the work,went to go back out from the dock and the boat was in forward,so I put it in forward thinking that was my reverse all I got was some grinding sound,So I took them out any way with just forward.LOL I made it but turning around wasn't to fun,Came home removed lower unit put shifter and lower unit in neural,same thing happened,then I tried forward on shifter and lower unit,it would not come out of forward,I'm not sure what I am doing wrong,or if maybe I didn't put lower unit together right,is there a easier way to put lower unit in were my shift linkage will be correct ,any help would be much appreciated!!Thanks in advance for any info."