Barnhard_Marine - thanks for the "expert/insider" comments & advice.
Maybe he was talking about that installation
tool you mention because it sounded like they had re-powered some boats in the past. But left them/port a couple of weeks ago, so can't follow-up to clarify.
Thanks too for the alignment tips which I'm familiar with but when he threw the part in about the other end of the shaft, I became very curious.
atoll - thanks for image link - & comments. Although your example sounds like it is on the Engine side of the shaft/coupling. The mechanic
was making the point about checking the other end first.
It was almost like he was concerned about length & angle as the shaft attached through the Dripless (or similar) Shaft seals
. Since I've never taken one of those apart I have no idea if there is an adjustment to lengthen or shorten (fine tune) a shaft at that end.........Just guessing/wondering based on comments & hands waving.
They were fine gentlemen & the mechanic was just expressing his desire to check everything. It never went further than the discussion.
Appreciate the responses, ideas and suggestions.