I think I would even make the backs of the box higher and maybe the sides taper down. I hate stuff tipping off the backs. We have one we keep all this tupperware like stuff in, for leftovers and you never dig to the back.
We have a tall pantry with slides and i was just telling her about converting ours over and before i told her she said i had a bottle fall over the back yesterday and had to take everything out to get it. LOL.