Online Community of Zenith Builders and Flyers
I've found that if I leave the finger prints on for more than a day or two they become very difficult, if not impossible to remove. I've been using some turtle wax liquid spray car wax on the part, and that will get the prints off if they haven't been on too long, plus protect it somewhat from future corrosive prints.
Don't know about Turtle Wax spray, but just a caution. Don't treat any bare metal parts with anything that has silicone in it (a lot of polishes do!) if you intend to paint it later ... it'll cause all sorts of grief!