Do the Edelbrock manifold and dual carbs!! You will be RE invigorated with dual carbs under the hood. People will stop and awe at the sight of them as well. You will be down in peak HP compared to a single plane with a big Holley BUT- the power up to 5900 6000 RPM is awesome. Low and mid is fantastic. The 2x4 setup is much cheaper than a 6 pack. Multiple carbs is how more power was made back in the day. Go new with the carbs to avoid headaches.