Don’t be afraid to grind on the heads to port match them to the intake gasket. If you’ve never ground on aluminum before, you’re in for a surprise as they cut very easily. Just keep the pressure on the burr that’s being used light. Don’t use stones. Also having some brake fluid handy to dip the burr into will keep the burr nice and clean. And be sure that the heads are fully disassembled so that they can be cleaned up thoroughly after the grinding takes place.
As far as the dual quad setup goes, here’s a past link where the factory ’57 2X4 setup was dyno tested bolted atop the aluminum heads.
http://www.y-blocksforever.com/forums/Topic46008-11-1.aspx

Lorena, Texas (South of Waco)