>Until I fully understand why electricity in the fuel
>tank does not blow,  I refuse to install the fuel sender.  Any input
>on this?

"Sparks" are usually either air molecules heated to incandescent
temperatures, or (sometimes) tiny bits of near-molten metal. They happen
when the electricity doesn't have a good path to ground and has to "take
what it can get", so to speak-- either jumping across open air, or
"squeezing through" a tiny point of hot-conductor-to-ground contact. In so
doing, the resistance it's pushing through generates a lot of heat. The
super-heated air will certainly ignite gasoline vapor (just like a spark
plug), as will tiny bits of white-hot copper. So long as the electricity on
the hot wire has a way to get back to ground that doesn't put up too much
resistance, no significant amount of heat will be generated. In the case of
a fuel level sender, so long as there's no way for the hot wire on the
potentiometer to arc to ground (and they're usually VERY well protected
against such things) there's nothing to worry about.

John Bange
'90 Vanagon "Geldsauger"