With the fuel delivery problem I had with my TR4 yesterday and thinking about road side repairs in the future, I was wondering if someone makes a small ball valve that can be used in the fuel line as a shut off valve for the fuel (with either the appropriate fittings of raw 1/4 inch hard lines). I was thinking of placing it in front of any filter I install as well as before the fuel pump. That way a quick turn of the ball valve lever and I can remove the filter and/or the pump without have to pinch off a fuel line or pour fuel on the ground.