After moving into my parent's house while our new house is being built my neighbor let me store my trailer in his back yard. Being that we now live 35 minutes away I asked him to tarp it for me before the fowl weather hit here back in October. When I went over to grab some stuff out of the trailer I saw he had used one of those silver and brown looking tarps. Little did I know that silver part was actually painted on the tarp and that was against the trailer. Well, through all the wind, snow, more wind, lots more snow, and some condensation it left my trailer looking like this...




Has anyone ever had this happen to their aluminum skin? Or know of a way to get it off? It looks like a grease smear but it doesn't come off easily.
Thanks for any help or advice!
Robbie