The Wire from the alternator stud goes pretty much straight to the battery and should be hot all the time. Between the main stud on the alternator and the battery are the following connections.

Alternator goes to a multi-wire disconnect located at the rear of the passenger side valve cover in the wiring harness. This was something that was started around 73 (maybe 72?) and earlier models do not have it.

It then goes to the bulkhead connector. (1st of 2 large wires)

From the bulkhead connector it goes to a splice buried in the wiring harness (the splice itself is rarely a problem)

From the splice it goes to the ammeter gauge.

From the ammeter gauge it goes to the bulkhead connector. 2nd of 2 large wires.

From the bulkhead connector it goes to the fusible link .

From the fusible link it goes to a terminal on the starter relay.

From the terminal on the starter relay it goes to the battery.

As you have said the fusible link will leave the car dead.

If you have any voltage at the voltage regulator connections then you should make voltage at the alternator stud. Since the connection to the battery is nearly direct you should have voltage even if you disconnect the voltage regulator. So, If the motor is running and you have no voltage at the alternator, then it means you have BOTH a problem with the voltage regulator, (bad connection or a bad voltage regulator) AND a broken connection between the alternator and the battery. Check the connector at the rear of the motor first.

Most common problems are the connectors at the back of the motor and the bulkhead. Check them first.