1975 360 budget build

4 bbl (600-750 cfm) & intake (dual plane)
Fresh heads. MPG and power is made by good sealing valves. If you are up to the challenge, mild bowl porting at home with a Dremel can get you a little more....
camshaft- keep duration in the range of 214-224 @ 50; lift between .444-.474.
A good dual exhaust system.
Tune and more tuning. Your are at your goal.