The Wife ordered magnetic signs for the cars and it put a permanent square in the paint, but I think it was because they were new and when the AZ sun baked them for awhile they off gassed or something.
Maybe the paint faded around the outside of the sign where it wasn't covered? I haven't noticed any color difference around the Roadrunner's cowl vents but it may be because we've got them cut to the same size & shape of the openings.
