Pictures of wiring please

There is several ways to go, depending on harness condition and your skill level, and purpose

1........Strip the old out, lay it out and nail it down, mark it, un tape it, replace all or some wires, rework the end terminals.

2........Buy a used one in good condition. They show up, obviously in various places........here, ebay, etc, Craigslist, and there are commercial sellers who deal

3........The "Year One" types that sell "repop" factory exact replacement harnesses

4........Any number of aftermarket "generic" harnesses, and there's a bunch. Painless, Ron Francis, American Autowire, Rusty on here is trying out a "Speedway" 20 circuit generic harness. I might get one myself. I have a Painless I bought "sort of used" that was in the car. There's a guy here locally (Spokane Craigslist) who seems to always have a 12 circuit generic harness. No idea where he gets them or where they come from

You can buy the connector terminals through places like NAPA, assuming your connector bodies are not melted, damaged, etc.

The generic harnesses lend themselves to radical changes......eliminating the bulkhead connector, going to electric pumps, fans, and EFI, etc, and eliminating the ammeter.

If you want "restore correct" then you'd have to stay away from the last