[swamp rat]

Originally Posted by '68OrangeSunshine

The most important detail about the HEI install is that you feed it full-time 12VDC. The Points distributor system has a Yellow 20 ga. wire going to the Coil Pos (+) terminal. This end, plus its other side, the Yellow 20 on the Starter, are connected to the Resistor wire Orange/Purple/White from the bulkhead connector. You will need to run a new line [I like Red] 10- or 12- ga. from "Ign.Unfused" on the Fuse terminal in the cab thru the firewall and right to the (+) coil lead in the cap of the HEI. The old line with the resistor wire will provide 12 volts initially, at start up, but as it heats up will increase its resistance; dropping voltage to 7-9 VDC, so the points don't burn up. HEI Modules will ... not function optimally... if not given their full 12 volts.
So you need a fresh wire. You can keep the old yellow wire in place, just tape it off, if you ever want to go back to points. Keep the other end Yellow lead on the Starter, that's still necessary.

Thank you for that!