what spark plug with vortec heads?

OK, i've got a '66 corvair convertible with a 30-over 327 where the back seat used to be.   i recently installed vortec heads from a '97 pickup, along with a chinese ripoff of the performer RPM air-gap intake.   static CR is 9.8:1, and cam timing is unknown although i've measured lift to be approximately .420 intake and .440 exhaust.   the car runs great as-is, but i'm in the process of really dialing in a sharp tune for next year's autocross and drag race season.

my questions are regarding spark plugs.   i haven't found a clear reference in any of the engine buildup articles as to which plug works best with the vortec heads, and how wide they should be gapped.

is it the cylinder head, the CR, the ignition system itself, or some combination of the above, that drives the spark plug decision?

real-world answers are appreciated.   thanks in advance,

patrick aka AngryCorvair@AOL.com

I USE THE AUTOLITE AR 473 PLUGS AND YOU WON'T BE ABLE TO GAP THEM,WHEN YOU GET YOU WILL SEE WHAT I MEAN