365 22 electrical failure

Hello-

I was driving my 67 2+2 when the engine hesitated, then died. A second later the throttle pedal went to the floor and black smoke started billowing out of the engine.

The throttle cable had melted, apparently igniting the plastic covering of the clutch flex cable. (Hence the smoke)

When I got home, I noticed the battery appeared to be leaking (this was after an overnight charge), and it looked like battery acid had corroded the main ground strap.

I put in a new ground strap, but as soon as I connected the batter, the positive battery clamp melted in two. Conclusion: short somewhere.

I connected a continuity tester from the positive lead and ground and observed a closed circuit (key removed).

I disconnected the positive lead from the starter main terminal, and the (marone) lead from the starte solenoid. Attaching my cont. tester to the starter terminal and ground also shows a closed circuit.

I figured this is impossible unles the solenoid is engaged, otherwise current would always be flowing to the starter windings and the car would always be starting. From this I concluded there is a short in the starter motor (or maybe the solenoid is frozen closed)

There is also a small guage wire that connect to the positive terminal, but doesn't go to the starter. It appears to feed the ammeter, and eventually other devices (e.g. panel lights, etc.) This also shows closed ciruit to ground. But I figured this might not be a short, since some things like the clock might always be drawing current (and I had the door and hood open).

So I got a 6V lantern battery and took an ammeter reading, which showed 10.5 A (I had no idea!) in dead short. I connected this to the battery cables and measured the current through small guage wire, which showed 1.5 A. I then measured the current through the starter motor-to-ground, and observer 10.5 A.

My conclusion--the starter is drawing as much current as it can (e.g. a short), including up to the ~60 A of my battery--hence the clamp melting.

My questions:
1. Is my reasoning correct, or just very plausible but wrong?
2. Does anyone know a better (systematic) way to debug this problem? I don't want to pull the starter and find out the short is somewhere else.

Any guidance appreciated...LT