Stop in for a cup of coffee

They switched to the 4 pin ECU box and single ballast resistor in the 80s. The later ECUs had the start circuit combined inside the ECU & no longer needed the extra ~5 ohm half of the "dual" ballast.

This is also why I said don’t ignore the ECU as the source of ignition problems. They fail all the time and are hard to test. I carry at least one spare all the time.