Suggestions on which plugs to go with

Scody 21,
OK, brain surgeon. My Racing Spark Plug catalog [ below ] is 1994, before Irid plugs appeared en masse.
Notice 'NGK racing spark plugs' at the top of the page???
Notice that some of the plugs had Plat centre electrodes AND Plat grd electrodes. Irid plugs followed.....around 1995-6.

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