I plugged in a battery charger to that hot lead, and found a good spot to stick the ground cable down on a motor mount...
The needle never moved: just as if nothing was connected.
I even "jiggled" that ground cable around a bit; thinking that some paint or grease might be in the way...
Everything is deader than a hooker's heart: up front.
EDIT: that hot lead is an excellently designed addition to the underhood stuff!