So I went out to the garage the other day and the battery in the '33 was totally dead, which is not good with an AGM battery... I'd pulled the battery tender off to use on the old truck some time back, and just didn't take time to bring it back and hook it up. Had to use the old "hook a known good battery in parallel" to get it to accept the charge, then just left the trickle charger on for a couple of days. It's back to 12.75V this morning, which is a good thing!