Thanks! I'm really looking for a box that goes UNDER that cover that yours is sitting on. There is a storage area down there - I would like to find a box that fits in there that would be big enough to accept my 12" sub. I know I need at least 7.5" for the sub - that's how tall it is. So, if it's in that cavity, firing upwards, I need at least 7.5" of depth, before the box. So, probably more like 10" of space when you add the box materials...