I'm sorry I may have been mistaken because I do not find resistor wire or ballast resistor mentioned on most of the 60-66 wiring diagrams I find. So please take what I say with a grain of salt. This diagram does appear to have a resistor wire, it is marked 20 W/OR/PPL, it would be a cloth covered wire and most likely faded to white after all these years:
https://67-72chevytrucks.com/vboard/...75#post2958975
If you think you have a white cloth covered wire going to your HEI that is most likely the resistor wire and should be replaced with a 14 or 12 gauge wire and you would not need the yellow wire going to the starter R terminal. Follow the wire and see what color it is and where it goes. There are some setups where it is common to go through a ballast resistor and may be a pink wire. For HEI you don't need a ballast resistor or resistor wire. You may get better answers from folks that know more than me by posting in the electrical section of the forum.