Bolting it to the floor might at least take the rocking out of it. A shop-built one I have is bolted to the bare concrete floor with washers as shims on a couple of corners to help level it.
This is the route I'd take, I'd also add some kind of very thin barrier between the carpet and safe, like plastic film (in case of rust)
A stand would likely have the same issue and be more dangerous.
Edited by Western (01/21/16 06:20 AM)
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