We were just discussing a really great Singer 66 redeye with nearly perfect decals that someone ruined by drilling through it to make a lamp. The damage is irreversible. I guess in some sense valuing the decorative potential of a sewing machine is a start in learning to value and preserve them but I figure they're better actually being used as sewing machines or displayed in a non-destructive manner. It would be no more difficult, in fact easier to have the lamp post behind or of to the side and the machine displayed in a manner where it could sew again some day.
Rodney