I was going through my engine harness for a swap while following some instructions from granny speed shop and using a wiring diagram. It said there were wires I could use for the ignition on a certain plug that connects to the front harness but there’s only one place it connects. Can any of these wires from that one plug work? I’m doing a Sbc swap

 

Whats the information on the car?

Edit - So your info says you got an 89 FC if that's right then I looked up a little info and this is the same stuff that I used to identify my connectors when I swapped mine. I hope this gets you in the right direction.
https://www.norotors.com/index.php?topic=2874.0