if you want to see what it'd look like, just buy some fake portholes from autozone and stick it to your car.
I'm not sure you can do this on the side of the car and not look autozoned out like you wanted.
Edit-
Although you can probably do something like this and not look too bad:
you just have to make sure you cut it and set it into the bumber right so it doesn't stick out and look bad.
You may even want to look into finding cooling vents for brake systems and direct the air flow or position so it blows into your cai.