It’s not in your wiring.
Running on is known as dieseling.
If your primary throttle is open enough to allow a bit too much air into the motor, a hot spot in your intake will ignite the air and a bit of fuel to make it run without the ignition on. It continues to try to run because the air going into the intake draws a little fuel from the carb.
Cure is to close the throttle almost completely.
There’s a section in this link which deals with the transfer slot on a Holley. Your carb is the same. If you get your transfer slot set you’ll likely cure your high idle and your run on.
http://www.crankshaftcoalition.com/w...EI_distributor