That combo is what i tell everyone to build for a true milder 440 screamer, Its old school & tried & true, remember back in the day when the Chargers/Coronets/RRs with 440s were tearing up the streets, that was the combo, but they ran a SD & 850dp., 3800 converter & 3.91/4.10 gears.
Buddy of mine had a 68 Charger with the old shool 446 & mildly ported 906 heads, ran 3.23 gears & a 3000 stall, the engine was set up to run a 38-4200 stall & 4.10 gears, he never installed them, Car ran 12.3s @ 109 with a set of slicks & un-corked exhaust on its 1st. & only pass with no other tuneing.
I'd ditch the stock intake for a SD, keep the 750 if its a DPer for now. If you can bang the gears with stickies, car should run mid 12s all day long if not better.