Ok, i cut the yellow wire in my fuel pump, and put in a 2 prong switch. In the Off position, i can start the car and in the ON position. What i noticed is the fuel gauge goes all the way below E (what most people say happens when the smoting switch works.) I havn't driven it around to see if it shuts off, but i left the car idleing and revved it a couple of times to about 3k in both on and off... nothing happens, car stays on.

Any ideas about how to make this thing work?

 

Sounds like you cut the wrong wire.

I'd be willing to bet you cut the fuel sending unit (fuel gauge) wire rather than the fuel pump wire. It's an easy mistake since they're so close to each other.

Take out your rear seat and look again. Take the switch out and connect those wires back together. Then find the fuel pump wires and run the switch to the ground wire in that pair.

Fuel cut-off shouldn't affect your fuel gauge in any way.

Justin