C158 wrote: Would there be any other way to prevent the prying on the sides without having to lock both sides?
Hmmmm

Definitely, with metal there is always a way. But from my idea of what you are building, idk How much of a issue this would be with it being 1/4 inch steel. they would need the jaws of life to bend it up. The shorter the length from the center (where the hasp is) to the corner, the harder it would be to bend. . It could always be reinforced on the inside. If you keep the gap between the top of the box and bottom small enough, someone would be less likely to be able to get something in there to pry it up.
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