If you are only getting 10 MPG you have issues that no ignition system will solve. 16-18 MPG would be more like it. 20 on the highway isn't out of the question.
A 1407 is a lot of carb for that combo, and Edelbrock jetted them "for performance". DOUBLE CHECK YOUR FLOAT LEVELS!!! Make sure the metering rods are staying down at cruise, and go 1 step leaner on the primaries (carb manual has good graph).
