I've finished up blocking off the heat crossover, gasket matching the ports, painting the bottom of the intake and plugging the injector bungs as a temporary fix. I placed some steel wool in the heat passage as a dam and then put in about 1/4" of J B Weld. That worked well on my 2x4 manifold. Then I found some small freeze plugs that fit the bungs fairly well, a tad loose, and inserted them with a bit of Black RTV to help "cement" them in. These will have to be removed when I get my fuel injection set up ready to install. They sit atop a ledge in the bung and cannot fall or be sucked in. There should be only vacuum on this area so unless there is a catastrophic
backfire they will stay put without any more persuasion. In the meantime I can now use this 7503 manifold with a 1407 Eddy. I still have the same engine components as with the 2x4's. It should be interesting to see how this compares! I suspect I may see more bottom end this way.
Rich Kinsley '64 Dodge Polara LeRoar 4dr 324 poly w/goodies