I have a '77 MA that I am going to tear in to next winter. I am going to replace the transom and close it in at put on a bracket. Cut my floor out and replace it but put my new floor on top of the old floor to raise it alittle bit. My transom and floor are solid but want to put a bracket on the boat anyway.
With that said, I would replace the transom.
And I have heard the same results with those moisture meters. Not very reliable in my opinion.
Interested in what you do and want to see pics of the process.
Thanks