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...I'm not real nostalgic about Italian paint and decals from the time period of this bicycle. I would strip, repaint, and re-sticker that bike in a heartbeat. Then clear over everything with 2 part urethane. There are translucent pearlescent paints available in spray cans from companies like Testor's (at hobby shops). If you want that effect, it's not difficult to achieve, but I wouldn't do it over the decals.