I have read on several forums that the new Sterilites will fit, you just need to remove the latches.
If the latches rest in a recessed area on the box this can be filled in so the boxes remain secure.
Otherwise, any plastic 3/8" or thicker can be cut to fit perfectly inside of a box. They can be held in place temporarily with screws and any silicone or hot glue that will stick to the plastic.
If silicone bonds to the plastic box well then you don't even need the screws. It really depends on the blend of plastic used in the box.
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Currently keeping:
6.10 Gonyosoma oxycephalum (Javan, mixed colors)
0.0.4 Rhynchophis boulengeri
1.1 Philodryas baroni
1.1 Lampropeltis triangulum multistriata
0.0.1 Rhamphiophis rubropunctatus
0.0.1 Morelia viridis "Aru"
0.0.1 Morelia viridis "Merauke"
1.0 Rhodesian Ridgeback