Fuel pump questions

[Ed]

Some of the questions I'm about to post may sound stupid, but I'd really
like to get some answers.

In-tank fuel pumps: Since the wiring is also submersed, would there be
any worry about the + and - wires shorting each other, causing a spark,
and destroying the fuel tank? (this is my dumb question)

In-line or "booster" pumps: One person tells me you must run it
constantly with the main pump, otherwise there will be such a large
restriction in flow. Then again, Sports Compact Car magazine has an MR2
project car that uses an inline pump that can be turned on or off,
regardless. Are there some pump designs that do not restrict fuel flow
if shut off?

Mustang in-tank fuel pumps: I'm looking for the OEM pump's fuel capacity
in GPH and what operating pressure is. It's the previous model Mustang
I'm talking about.

-Ed