The very first thing I did on my car was gut the airbox then I drove for a day or two till I picked up a K&N. I noticed slighty more boost with just gutting the airbox becasue of that restirction which was removed. & upon adding the K&N the increase was greater. For the most part you aren't going to increase air flow much by doing this it will just lessen the restriction of incoming air. There are fender well intakes for our cars you should check out Intense'* website, also search for "FWI or CAI" and you'll see many pictures of people with aftermarket air intakes.
1998 SSEi The Executive Hauler
Built Trans w/ 3.29s, P&P Jenny 5, S1X cam, Silver TOGs, Northstar TB & LQ4 MAF, FWI, Dyno tuned, #60 injectors,Oil Pressure Kit, 2.9-3.4MPS, MagnaFlow exhaust, 3" HF cat, MSD Coils & 8.5mm Super Conductors, AeroForce, only Sunoco 94, 100