I like the ThermoQuad, too, but if you decide to use one I think you'd be happier with a spread-bore manifold rather than trying to adapt a square-bore intake. I tried that with my 360, and it just didn't run very smooth. Poor fuel distribution compared to running a spread-bore. At cruise with constant throttle, you could feel it miss slightly. That went away when I switched to a spread-bore manifold (Edelbrock Performer). Unfortunately, I don't think Edelbrock makes the Air Gap in a spread-bore for the Chrysler small block, do they? If you're going to use a carburetor with those big secondaries, you sure as hell don't want to choke it down with a square-bore intake.