The biggest thing you can do to help a 440 is slow down the RPM either by reducing speed or gearing higher and locking the converter, higher gears don't do much if you just slip the converter more. If your building a motor than run as much compression as you can get away with, enough compression to require premium fuel helps MPG enough to cover the extra cost in fuel, any tricks to permit more compression helps also like a source of fresh not underhood air, air gap style intake with no crossover, tight quench with closed chamber heads, fully radiused and polished exhaust valves, sodium filled if you can find them, ceramic coated exhaust under the hood retard cam timing a few degrees. An 850 thermoquad (800 gets into the secondaries too much even cruising) done by someone who really knows how to tune it will do better than a holley. Very little if any cam overlap and as much lift as possible heck some 1.7 rockers on a stock cam would work great. Well tuned spark timing (they like a lot 20 idle, 40WOT 50 or more cruise). Run a 3 angle valve job on the intake to break up fuel droplets.

I know I will get flack from old timers on this but I used to always try to run smallest ports I could find for my MPG motors but eventually found out it didn't help in reality and just killed any chance of getting a few RPM out of a motor (probably the only reason they ever APPEAR to help is you CAN'T turn any RPM), actually the opposite as I have hemi heads that flow 330CFM on my 2011 ram and it can get 20 on the highway empty. I would even run a maxwedge port on that and the longest runner, matching intake manifold I could find.