Here is one for the group interesting problem

Just crimp a ring connector on that wire and drill a small hole in the lip of the tank, use a self-tapping screw to secure it. The bent up corner is the best place, put a piece of wood behind it when drilling so you don't drill through the tank though.
 
Just crimp a ring connector on that wire and drill a small hole in the lip of the tank, use a self-tapping screw to secure it. The bent up corner is the best place, put a piece of wood behind it when drilling so you don't drill through the tank though.
Make sure you drill the hole outside the weld. If you drill the hole inside the weld you could cause a leak.
 
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