Looks awesome. Does Evaporust only hit the rust or does it ever eat into the metal a little bit too? With those little bumps music boxes have, I would've wondered if it was safe to use on that. I assume it probably is, but the thought crossed my mind.
I guess it would matter more if the bumps held some kind of tune and even a microscopic difference could throw it off, but they don't, so even if they get worn a little all I think all it would do is affect volume/intensity.