1945-P Jefferson War Nickel Clipped Planchet (Verification, Conservation).

I picked this War Nickel up for $9 on ebay. I really liked the luster of the coin. It appears to be a legit clipped planchet, although it was not sold as such. There is a visible Blakesley effect, although not so much Smith effect. More metal flow at the edge of the clip than a strongly curved rim.

The coin did not arrive in great shape. It had been stored in a plastic flip for some length of time, probably in a humid environment, and there was a neon aqua colored film around both sides of the rim and a big splotch right on the bust where it was touching the plastic. Mostly the film wiped off with a tissue, but I am concerned that the residue will begin to damage the coin. I don't really know how to handle that, as I assume that pure acetone will also strip the toning right off. Advice?