Custom tool storage?

Searched the forums, but no luck. My question is about the empty space which used to be occupied by the airbox, once you have converted to pod filters.

Has anyone ever utilized this space? I think it would be a great spot for a custom storage box, aluminum possibly, for tool storage. I have a tool bag which is too large to go under the seat, so I keep it in a tail bag, along with spare clutch cable, chain lube, and a couple of small containers of brake fluid and motor oil. For shorter trips close to home, I prefer to remove the tail bag, but then feel naked without my tools.

Tried a square Tupperware container, but it just didn't look right. Any hints, photos, tips appreciated.

Not that I have done this, but how about leaving on the airbox, closing off the carb openings, and using it as-is? On my twin, there is a nice screw-on top, and it would hold quite a bit of stuff. Guess the trick is to make it water-tight.

I think I considered that, but if I remember correctly, the filters are longer than the boots in the airbox, so it wouldn't work. Too bad; as you said, it would hold a fair amount of stuff. Another item for the to do list.

I bought some sort of emergency road bag at Advanced Auto Parts. It is almost kawasaki green. Game with jumper cables and first aid kit in it. Stuff like that.. It fits perfectly in that space and holds all the tools I need. I'll see if I can take a pic of it later.