I've done three of these airboxes and should mention a couple of things here. Be real careful around the headlight faom seal so you don't accidently mess it up. Remember it is there not only to prevent any hard banging on the body, but keep unwanted hot air from being sucked into the intake. If yours is old or you mess it up during the proceedure, then a visit to Home Depot will net you some replacement foam in the window weather stripping section.
The other thing to watch for is, cutting without looking where you are going threw the other side of the cut. Since the box has peaks and valleys, one could easily cut though a V section and leave a hole to the outside hot and/or unflitered air.
The last box I did for myself, I used a hole saw and cut a hole on the fender side (pre-filtering), mounted an AutoZone circular adapter, and attached a 2.5" hose that ran down into the fenderwell. I'm assuming this gave a little more cold air flow.
I dont have a picture of the additional cold air inlet, but if my wife can find her camera I'll add a shot of it with the hose.
