I am replacining my stock 4V manifold (4V heads) on a 351C with an Offenhauser intake. When I got the old manifold off, there was a metal pan between the intake and the lifter cavity. The replacement gaskets include the gaskets that seal the entire manifold but do not include a pan. Do I need the pan? Seems redundant, but the pan was the gasket that was used with some sealer. Any help on installing this properly would be greatly appreciated. Thanks!