318 MAX fuel economy builds?

Elec ign conversion should be on the list. At the top. It has two important benefits that aids mileage & performance:
[1] it does not start to retard the ign from day one like points do because it does not have a rubbing block that retards ign as it wears. Retarded ign hurts performance AND mileage.
[2] you can run a bigger plug gap, which exposes more of the A/F mixture to the ign source, which is the spark. The best/simplest/best bang for buck system is the GM HEI conversion with a an E core coil such as the MSD #8207 & run 0.060" plug gaps.