One wire alternator conversion- best method to run the thick power wire

Low route exposes the cable to elements, oil, potential road hazards depending on routing. The length is not that much different and pretty insignificant when it comes to performance in almost every case with a properly sized cable.

JMO, nothing smaller than a 6ga cable on that install. Really a 4ga would be better.

On a one wire, the main charge wire provides the sensing for output. So the cleaner the signal back up the wire the better.