Now that is a crazy question.
I'll go out on a limb here and assume that when you talk "Infrared," then you are talking about some sort of covert IR illuminator to use with night vision goggles. Since I work with NVGs a lot as a part of my job, I'll give you my take on it.
First off, it would be pretty easy to modify a set of foglights. There are companies that sell filter material that you can cover your lenses with that will emit only an NVG-friendly spectrum. You'll get a slight glow out of the lights, but for the most part it will be hard to tell that these lights are on. Also, there are also companies that sell IR bulbs, which IMHO would be the best way to go if you can find a set that will fit your application.
Now, on to the practicalities.....
If you are planning on using NVGs, there are a few things to consider. First and foremost, they are not the most comfortable things in the world to drive with. With the exception of the latest military versions, the field of view is quite tiny and you'll be required to move your head a lot to see things around you. Forget about peripheral vision....it is nonexistent when you're wearing NVGs.
Another thing to consider is your interior lights. Any light in the cockpit will cause the NVG's to "gain" down and will hurt the performance of your goggles significantly. I'd make sure that either the lights be covered with a green NVG-friendly filter or turned off altogether. Exterior lights, including streetlights and lights from other cars will do the same thing to your goggles.
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'91 Black/Ivory NSX
'89 Gray/Gray F-16C
