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If you don't want to go through the trouble and expense of fitting the cone and fabricating a heat shield, or you don't want to increase the intake noise much, there is an alternative. You can improve the stock air path by simply replacing the 9" puffy hose that connects the air intake panel (behind the headlight) to the air box with something larger and smoother for better flow. For an investment of about $10 and a couple of hours you can improve one of the intake system's weak spots.

It just so happens that 3" black ABS pipe and fittings are nearly a perfect fit for replacing the intake air hose. Go to the plumbing section of your local hardware store and get one straight piece (you only need a few inches at most, but a 1 foot piece will make it easier to cut) and a 1/8 yard elbow (1/8 is the amount of bend in the elbow joint). The yard elbow should have a male end and a female end, not two females. You'll also need some epoxy, and some ABS glue.

Take the skinny end of the yard elbow and cut off it an an angle, removing about 5/8" more from the pipe on the inside of the curve. This allows that end of the elbow to go into the panel behind the headlight at a slightly increased angle. Now cut about 1" off the female coupling on the elbow, then cut a roughly 1" piece of the straight pipe, to fit into the female end of the elbow. This should leave about 3/4" of the straight pipe sticking out. You can remove one of the mating rings from the puffy hose by unscrewing it, and use it to mate the straight pipe to the airbox. Put everything together and mount it on the car to see if you need to make any adjustments. You may need to adjust the cut at the small end of the elbow to fit the panel.

Once you get this far, you can set the intake panel in place with the pipe resting in the air intake, and glue the joint between the pipe and the elbow, making sure everything fits (use ABS glue - it's less messy and sets faster). Finally, remove everything, place the mating ring on the lower end of the pipe, put everything in place again (just to be REALLY sure it fits) and epoxy the mating ring on the end of the pipe. When the epoxy sets, remove the whole thing, and file and sand the mating ring and epoxy so it's flush and smooth with the inside of the pipe.

You can open up the intake port behind the headlight by cutting off the plastic ring on the panel and a portion of the incoming elbow so that the opening is flush with the outside of panel. This opens up the fishmouth considerably, and gives a desirable diagonal opening into the pipe (cuts potential resonances).

You will be able to remove the panel just as before, except the pipe may be more difficult to move out of the way. Spray some silicone on the mating ring at the bottom to ease future removal.