[eschaider]

Joel,

Something to consider on the fuel return line;

If you put it at the bottom of the tank, fuel will run up the return line and force the return circuit to overcome the pressure this fuel presents to the returning fuel. When that happens, it will cause an artificially rich condition because the fuel pressure regulator can not return all the fuel it needs to.

If you plumb the return line to the top of the tank or near the top, the return line does not need to push against the fuel weight in the return line and tank to return. The engine likes its fuel delivery better when it is closer to stoich.