The manual says that's to be expected(?), according to Bob(new owner).
He's replaced both the temp and oil sender, with no change. The engine seems to run fine and doesn't appear hot so he'll look into electrical problems before he starts testing actual conditions.
He thinks there may be a problem in the ground as he found lack of continuity in something(I just stopped for a few minutes). Said batteries were replaced so I thought he should check to see all grounds were re connected. Thanks for all the ideas.
BTW, a Nonesuch 30 is the biggest 30'er below, I've ever seen.