Its a shame a dual carburetor under hood intake manifold is simply not made for the 340 360 mopar. Offenhauser still makes a unit but its design is for the 273 heads. It will bolt to 340 heads but its not ideal and its a design from the 1960s. Ford and Chevy have dual plane dual quad manifolds in traditional and airgap versions and from multiple manufactures. I like tunnel rams but I really like under hood dual quad setups. Harkens back to a time where to go faster- you absolutely had to add another carburetor!