What would you do? Slant performance

1st question, what are we starting with, year and car?

I would not get too exotic. Mill the head about .080, get a good valve job, get a cam in the 250 to 260 duration range, matching valve springs or 340 valve springs, OEM Super Six intake carb and throttle linkage and kickdown linkage, Double roller timing chain, electronic distributor, Chrome ECU, custom exhaust single 2 1/4 pipe and straight through or other high flow muffler. You will now have good power and better mpg.