Rebuilding a 74 Duster - Kinda...

Welcome to FABO, this is a heck of a first post!
If money's not an object, i would go big block for sure.
A 400 stroked out to 451, 727 auto trans with a 3500 stall converter, 4:10 dana, super stock springs, pinion snubber, mini tubbed and some wide 15'' tires should get you there to beat that Ford, It would rev quick and have lots of torque.
Or you could go for a 528'' gen 2 hemi with all that i mentioned if cost isn't an option.
You won't get decent mileage if you want to have a cammed up street car, unless you detune it and put nitrous on it for the occasional blast.
I hope you plan to keep the car's color green!