You know... this concept is nothing new. Take a look at my Norton next time you're at the shop, Mark. The Commando "airbox" is really just the "velocipod" with permanent ends sandwiching the filter in place. there's a rear plate the K&N filter butts up against, then a front plate with two holes in it the carb boot stacks attach through. Sure, it's not the exact same design, as the filter is still separate from the plates, but I think the advantage there is that the filter can be changed without having to buy the whole assembly.
I think that exact same method could be used on a CB, using a couple plates of aluminum or plastic. This is, of course, if you think it looks really cool to see the filter media for some reason...