Thanks for the replys all! In my mind, I was thinking about the AMP tank and how that worked. If there was some way of accomplishing the same result.
wonner -- You are right. Its an expensive "what if". That billet box just seems like a REALLY nice mod and I keep going back considering purchasing. I just have never been a huge carto fan.
Dakota -- Thanks for the welcome. You are right, they do not have the filler material. Without any real knowledge of the product I had an idea in my head that the AMP tank would be similar to the setup of putting a 357 in the Billet box. However, I do realize that there are probably many differences that I have not accounted for in my musings.