I have a Mercury model 1150 I am trying to put an lower unit on. I have 2 questions. It likes about 3/4 inch going all the way up. It is not the shift or the water pipe. I can tell that the drive shaft splines are goint partly in the motor but it stops short of bolting all the way up. Also the other unit had the shift that goes only about 30 degrees each way and this one goes almost all the way around. I have followed the manual but it does address these 2 issues. I appreciate any help.