Starter wiring

At the starter, on a Mopar, it's impossible to screw up.
At the battery, same deal.
At the starter relay with the factory wiring and ends, it's still impossible cuz everything still only fits one-way. But after 40 to 50 years, the wire ends may not always original anymore. But ...it....still... doesn't much matter cuz the signal side of the relay works either way. But if this is where you are having trouble,then; the Mopar relay is labeled with 4 characters;
B goes to the battery,
S goes to the solenoid, the small brown starter wire
G goes to ground thru the safety switch, and
I goes to the ignition switch "start position"

But I suspect you have switched to the mini-starter with the side-by-side connector. With headers I think you have to unbolt it, cuz it gets really close to the metal pipes.With logs it can stay.
In either case; what rigger said.