Sounds good. Perhaps better for the group to stay where they are and the winner alone goes to the box to retrieve it but has to bring it back to the group to open it before they can get clothed.
then gradually the clothed players will outnumber the nude players.
especially good to have one player who will remain naked whilst the group return to their real clothes. Maybe that player (or two) have to have their real clothes destroyed and only able to return home in disposable garments? Or is that too much? Or of course other players may take pity on them and share clothing to make sure all go home in some level of being dressed.