No matter where you put the switch,it belongs in the ground side.Nobody has ever shown me one good reason to put it in the hot side.A couple of the problems I've seen were from putting it in the hot side.I saw one hanging off the starter in one of those cheezo teardrop shaped tabs vibrate and fall down.It just shorted and killed the car.I saw one on the firewall that had the cable pull out of the lug,and drop down to land on the flywheel housing.It shorted and melted the advance rod on it's way down.That one blew the battery up.We kind of suspect it was being pulled down by either the clutch or brake pedal.I saw one of those plastic switches melt and burn a small bulldozer up in front of my garage.It had the switch in the hot side.Once the cable had melted out of the plastic it dropped on the steel fuel line and just kept arcing.