I done the same thing I put in the screws in the small holes on the side of the box and if done right it will not affect the whole thing at all.
Just remember if you use two device mud ring just watch out with produited screw head that is the only quirk I have to watch out otherwise not a issue most case unless you get 277V in the box that will upper the anite a bit.
Merci.
Marc
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)
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