Be very careful with this. If you cut the fuel, but the pump continues running without fuel flow, it wipes out the bearings and brushes. This type pump may not gravity feed. Gravity bench check your pump, to confirm what you have....read my 3rd paragraph if your pump has free flow.
If you dont think this can be ugly, check out the number of people looking for "good" replacement pumps for their EFI bikes that they goofed, and "ran out of gas"....never to run again. I really, really, dont like to see an EFI pump run out of fuel....that is the lubricant for the armature bearings and brushes as the gasoline flows through them.
You may wish to be certain that the fuel pump power shuts down before that mechanical valve chokes off fuel supply. I plan to run a secondary "fuse blow" kill function off of my Pingle Guzzler valve, to be sure that I keep that expensive pump alive. This will short circuit the "relay control coil side" power and blow the fuse for that portion of the circuit, as the Pingle rotates. Fuses are cheap, and if I am smart enough to remember to turn off the fuel pump relay circuit, before pulling the Pingle lever, I wont need many fuses.
If you are not confident about your pump circuit kill arrangement (as when connecting to a manual shut off), you may be wise to avoid a mechanical shut off. Your grounding type tether switch, wired to the fuel pump relay control side power (after its fuse) will blow the instant the tether is yanked and the pump will absolutely stop. The rules already require your master electric shutoff control on the handlebar. Adding mechanical cutoff could be an expensive mistake if not taken to that extra step I mentioned.
Apologies for the discombobulated post....kinda hard to explain without waving my hands around in the air.
JimL
Added note...this might be another way.
http://www.12voltfuelvalves.com/79-afc161.html