Colder plugs...yes. Gapping down...no. Everyone always screws with the gapping sizes....stay with the stock gapping settings...it's there for a reason. However, if you have some type of dyno or A/F chart proving that gapped down plugs assist in more POWA...then post it otherwise I can't agree with you. BTW- You didn't even mention a re-gapping size...got a size in mind?
Sorry to be technical about it but we just try to keep bad recommendations off the site.