Smoke!!

While IMHO rats chewing wires was more of a problem 50-60 years ago when wiring had cloth insulation—instead of the plastic we have today—I’m not sure how important the possibility of those chewed wires/presence of rodent turds were to your situation.

As I said, don’t discount how weird “dead” batteries can function. I’ve heard stories of “dead”, supposedly non working batteries that have blown fuses, burned out functioning light bulbs, messed up distributor contact points (remember those?), and so on. Apparently it has something to do with voltage spikes that can be emitted by the battery’s good cells.

Yeah. To be honest, I'm a bit nervous about trying it back in the TC, even though it tests OK. It did something like this to me before - discharged completely.. but that time I was able to recharge.. I assumed I must have left headlamps or something on. No idea why it went haywire this time. If it is dead, kind of ticks me off.. it's only 2 years old.

The green fusible link is the charge wire from the alternator. It's possible you have a short inside your alternator. Hope this helps.

^^^^ Yup! The short is likely due to the 1 or more of the 6 diodes in the alternator being fried.