Very helpful, thank you! I'll check the rod to end of spool first to make sure I'm well below 25 Ohms before moving on in case I mess up the spool or connectors somehow.
Yes. Especially on inverter/communicating systems. Bad ground reference points can create a lot of havoc. Usually not as easy as the video as this was a new home. But I always carry that spool of wire to checking grounding. Good luck.