Unless you are tuned for the 180* stat, leave the stock 195 in place. And you want the hottest spark possible, so dropping 4 heat ranges would probably not be in your best intrest. Either run copper or the stock irridiums and call it a day. Oh, and don't over oil the K&N as they are known to coat the MAF sensor wires and cause issues. Also be sure to run at least 91 octane fuel.
4) Spark Plugs - Change out those stock spark plugs with new ones to restore any lost power. Brands that most tend to go with are either Copper Core Autolites or NGK's. They range as follows in order from hottest to coldest plugs...remember...you want the hottest spark you can get away with...so running a super cold plug on a larger pulley to combat knock isn't the best plan...OEM replacement ACDelco's, AL606's, and AL605's are basically for stock cars or very small bolt-ons still running the stock S/C Pulley or modded N/A guys...you want to keep a hot spark. NGKTR55/AL104's for your 3.4" Setup, TR6's are a tad cooler...best used around the 3.25" pulley area, and AL103's...are for the extreme supercharged application...3.0" pulley or lower. Here is a picture to reference the firing order and the correct coil number if yours aren't numbered or you just need a quick reference picture: http://i33.photobucket.com/albums/d6.../plugwires.jpg
AC Delco Factory Replacements: Stock
Autolite 606: Stock
Autolite 605: 1 Heat Range Cooler
NGK TR55: 1 Heat Range Cooler
Autolite 104: 2 Heat Ranges Cooler
NGK TR6: 2 Heat Ranges Cooler
Autolite 103: 3 Heat Ranges Cooler
