I haven't followed the whole thread, but in response to the original question, boatered forum is the best mercruiser board that I have found. There are guys on there that know Mercruisers like the guys on here know our boats, and they will see you through a problem with genuine interest-Ab-definitely go there-they have bailed my sorry a$$ out of a few problems. They are serious experts. We I/o guys gotta stick together. Dying breed on this board
I finally joined the board for 20 bucks which allowed me to search all of their archives. You need not pay to post or receive feedback, it simply makes your life easier when looking up a problem.
Who are you using on LI for your mechanic? I'm not so sure I am happy with my guy. I have learned to do a lot more myself on that board, though.
Good luck.
Doug