318 MAX fuel economy builds?

Great thread. I am building a 67 Cuda and i'm putting an A-500 and a 3.55 gear this spring. I'm building a 360 for it right now and am looking at high mpg as a big part of the goal. Thinking of running 273 bushed rods to reduce rotating weight. I'm looking for a set of 920 heads and I plan to port them and put larger valves in them, hard seats and bronze guides. Running the KB step up dish pistons get me around .040 quench and I will be running the Performer manifold port matched an air-raid 1" 4 hole carb plate and an Edelbrock AVS 650 annular venturis with the Edelbrock distributor as it's tunable both mechanical and vacuum advance. I'm looking at running a cam in the 215 to 220 at .050 range and I'll be running Rhoads lifters to get it back close to the factory 2 barrel cam specs below 1500 rpm. This is what I thought may get me over 20 mpg and still have some git up while I build my stroker. Thoughts?