charging and boiling battery dry

The ammeter should show a little bit of charge all the time. There should be two wires hooked up on the little plug, one is excite with diode that goes to ignition, the other is the sense which should go to the output post on the alternator. It is possible that the alternator is bad, but not likely. I would make sure you have good connections including grounds. It is also important to check battery voltage in case it is bad.

On Alternators the "Voltage Sense Circuit" must be in place, working and wired correct so it can register battery voltage so it knows when to slow down the charge rate. I don't know what you have, One Wire or Three Wire Alternator, but the old three wires had the 2F voltage sense connected to the battery.

Check with the seller they may just get you a new one.

John T

The test would be to check the voltage across the battery terminals with the engine revved up to at least mid RPM's.

Any reading above 14.5 Volts or so would point to a bad (internal) voltage regulator.

A lower reading, perhaps 13.5 Volts, or less, with the battery boiling would point to a "bad" battery. (Shorted or leaky cell.)

John T