I have a A1000 pump and had to run a new power line, but if you have a stock pump I would just try to find a wiring diagram and see where the power wire goes. Cut it off somewhere and add a switch somewhere out of the ordinary.
edit: not that I know if it makes any difference but I like the hidden fuel only as opposed to both fuel and ignition. That way if they try to start it it should run for like a minute or so then it will shut off and they might just think it needs a tune. If you have disconnected the ignition it won't even start and might piss em off and they might beat it up.
As for the GPS, that is incase they flatbed it