Use a felpro 1415 on the exhaust side, and a 1250 on the intake side.
Use a dye around the ports, then center the gasket on the head as good as you can, and then scribe lines around the inside of the gasket ports.
towards the bottom of this page has some pictures of my P heads in the porting process
http://stangnet.cardomain.com/id/fiveohpatrol
That aluminum should be ALOT easier to port than these were
