Power adders matter. Boost or nitrous will run a smaller gap.
Bolt ons don't matter. An upgraded ignition might allow a larger gap. Ideally you want to run as large a gap as possible to present a fat spark to the air/fuel mixture. Larger sparks are harder to maintain. But pullies, fan, intake....no need to adjust gap.
Best plugs for n/a 302 efi are stock ford copper plugs.
+1 I used to run motorcraft platinums. Now i'm running the coppers and it runs 10 times better. My rough idle is gone and at WOT it soooo much smoother.