On a baked duracoat job, the only thing that can strip the coating off is a ton of NC brake cleaner and a lot of elbow grease, or aircraft stripper. I've had CLP, small amounts of brake cleaner, and all kinds of other chemicals spilled on my duracoated guns and never had a problem with the finish coming off...once its been baked and cured.

I did do a gun once in Krylon paint for a guy because he needed a cheap refinishing, and it seemed like anything could take it off. I wouldn't recommend any kind of thinner or solvent on Krylon or similiar paint.