64 barracuda fusible link

64longroof said

Mattax, is it necessary to have a fuse link on alternator output wire if there's one on red batt. wire at bulkhead? I could see where excess alt output could overheat wires before current exits firewall and hits that "batt" red wire fuse link at starter relay.....but please correct me if I'm wrong.
Nice diagrams, by the way. Thanks.

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High current can overheat the wires and a fusible link is really no protection against typical high currents.
To melt a 16 gage wire quickly takes ALOT of current. I don't know the amount, but its got to be in excess of 100 amps.

The fusible link protects against battery positive shorting to ground. A battery can easily provide 100 or 200 amps (thats what's needed to spin the starter). It's just like uncontrolled arc welding if a wire (or your wedding band) accidently grounds any of the main wires. There's nothing to shutoff the spark show. So that's what fusible link does - it disconnects the battery.

Putting a fusible link in the alternator output is adding a restriction to the line.
In most cases when there is a short in the main, the alternator field won't get any current. Nor will the ignition. Either way the alternator is no longer capable of generating power. All of the electrons are taking the short cut and avoiding work.