Re: Both resistor wire and 2nd 12V wire to + coil at same time?
The yellow wire is open ended in the ign run position.
Solenoid energizes pushing the disc against the bolts completing the path for starter motor to work and the R terminal on the solenoid cap.
The yellow wire has power on it is at START position, regardless of year, by design, providing battery power to the ign circuit of an operating temp engine, ie, hot start.
This 'extra' power aids in rapid start, hotter spark, as the resistive wire, in a previously ran engine, is already hot and has reduced voltage input to ign circuit making for a weaker spark.
This is the only purpose of the yellow wire, aid in hot start for a faster start.
Sixty-seven's, I believe, have no IGN voltage from the ign sw in START position, thus the yellow wire is needed.
For all practical purposes for any year, the yellow wire can stay, just a shorter path for START ign power.
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