No power at ignition switch.
What are you asking me for?:D
You are the one helping him, and I just pointed out what he said about how it happened that was either misread or misunderstood.
But since you asked, he either blew the fusible link if the system is all stock then the bulkhead connector would be the next suspect, then the amp meter connections.
If it took more than that it would be any other connectors in the main power supply wiring or the wiring itself.
My personal bet is a 40+ year old fusible link.