And there are are books dedicated to the subject of hidden compartments:
(all found on Amazon)
The Big Book Of Secret Hiding Places
by Jack Luger (Paperback)
Secret Rooms Secret Compartments
by Jerry Dzindzeleta (Plastic Comb)
Handmade Secret Hiding Places
by Nonny Hogrogian (Paperback)...
FYI: interior coating and detailing ideas for restored or new tool boxes.
When I got my new Craftsman carry tool box and then a few years later a new roll around three box stack combo, I detailed it out by removing the drawers and cleaned the interior surfaces with alcohol to remove any...
New to this thread (and forum) and I have to say that is a great thing you did for your daughter. If she does take up a mechanical trade she wouldn't have to worry about her tools getting ~borrowed~ by most others in a shop though with the pink accents...