You should remove the HEI wire from the harness, and add a resistor wire that goes part way to the engine, and resumes in 2 yellow wires that go to the starter R terminal and the coil. You would probably be able to get that wire from another member by posting a want-to-buy ad in the parts section, or dig it out of your stash if you have the original harness. Harnesses can be unwrapped and re-wrapped because they usually have non-adhesive vinyl tape.
This is the wire you would be putting in. The junction shown by the dot is inside the wire harness before it gets to the end of the wrap that attaches to the engine at the transmission bell housing wire clamp.
It is the white cloth-covered resistor wire that you would use to replace the wire at your firewall plug, you may have a pink wire there now.
Squeeze the terminal like this to release it from the connector.
You'd be doing the opposite of this job, where if you had an orginal harness replacing a points distributor resistor wire with an HEI wire.
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