May have to do the same for my current Dremel.    Yours gives me lots of ideas.   
Do have an old Dremel #3 I think in a metal box.    It was Dad's, kind of small for bits and accessories.   Bits stuck in a piece of foam.     But it was Dad's.      Keep it the same but mine needs a wooden box as well as all the bits and discs etc.   Thanks for posting.  

Ron