Top box looks similar to a machine mart one I had a good 10 years or so ago.
That’s not any snap on topbox I’ve ever come across.
I’ll repeat what’s said it’s not a snap on.
A quick easy way to tell is if it has aluminium drawer trim the snap on is a solid extrusion pinched over the drawer lip. It’s the only way they did it on all their boxes post 1990. Before then there was no trim at all on them.
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