When my father was drag racing his supercharged 57 Custom he was running dual fours with the blower. The two bonnets and the fabricated inlet 'Y'  are shown in the picture below.  The bonnets are original Ford pieces. This was used with a factory dual four manifold.  The car is being restored to factory condition so I am selling these parts.  I am asking $1000 for the three pieces.   Located near Pittsburgh, PA