plugs for supercharged 3.4?

I need new plugs for my tacoma. It is a 2004 with a supercharger. Seems to be running lean now...I hear a slight ping if I put it to floor. I run 91 octain (all that is available here) and Im at 6000 ft altitude. Any suggestions from the pros?

 

Ive heard you should run the Denso Iridiums for the Chargers. But I thats just what Ive heard.

 

I've always heard to stick with the toyota stock replacement plugs, but im not 100% sure either.

 

just a question, call toyota and find out if plugs for a S/C 3.4 are the same as a N/A 3.4, if not when you buy either buy the toyota for S/C or go with an iridium plug

Ryan