If the engine is an RB, use the Indy dual plane. If it's a B, use a single plane and make the best of it by camming the motor correctly. Another alternative would be to port the RPM if you're trying to keep up with the heads. Hughes Engines' site has reference flow numbers and comments on various aftermarket intakes.

Dollar for dollar, I don't think much is going to touch these heads in a stock port window street application, out of the box.