Guys the problem with that last diagram is that depending on how big the alternator is, and it doesn't have to be "that" big, the small set of switch contacts may not be and probably are NOT large enough to safely handle the alternator output.
What I recommend is use a 4 terminal (correctly known as 2 pole switch, or DPST) and use the small terminals to break the fuel pump if EFI, or the ignition feed via a relay
