Well you can make one, and it'd look cool, but it may cause you serious induction problems. Some folks have made an enclosed airbox like this with no problems, and others like me have tried them and found there's a big flat spot in some part of the rpm band caused by reversion or some other wave phenomenon. I prefer an air cleaner backing plate that seals off the headers with a horizontal plate to the inner fender and a vertical plate to the hood, incorporating the entire stock backing plate of course so you can legally use the velocity stacks. I'll PM you a picture you can post for the group of what I'm talking about.