I'd use something a little bit better than cheap rattle can Krylon clear from wal-mart,atleast use Dupli-Color,or stop by auto paint supply store and buy a better grade aerosol clear that is made for proffessional touch ups and small parts refinishing,just about any paint line has their version of aerosol clearcoat ,also keep in mind that applying clear over cheap metallic rattle can paint will usually alter the color, so do a test panel