Grounded Tach Wire Creates a Gremlin?

Finally got back to this "issue", charged the battery overnight 2 days ago, this morning had 12.8v at the battery, ran engine and all is well, Ammeter behaving in normal range. I wear many hats as a business owner, one of them is "risk management" aka Michael Clayton and I think over the years I've become predisposed to see problems bigger than they are. I'm glad this was simple and sure appreciate everyone chiming in here.