They are 12V. The two batteries are for more amperage. Only the military Chevy/GMCs were 24V, unless there's something special that I don't know about.Does the starter really use a 24V system? I always assumed the batteries were in parallel at 12V
It didn't take me long to think "wherever that's at sure gets A LOT more rain that we do here".
He says it's in Bernardston, Mass within the first 4 seconds of the video. Though he talks so fast I had to google it like 3 times to spell it right...That yard is in mid America as I recall