Need help with spraying gloss over decals

Hi, I seems to have aa problem with sraying clear gloss over decals after iv'e set them on my car . Often times, the decals will have air bubbles in them, or crack, this happens with Tamiyas clear gloss. Iv'e used Testors gloss, but the surface is bumby after it dries. Iv'e used Model Masters Lacquer, but more bubbles. And model masters Enamel clear, but it makes the paint run. I dunno, maybe I'm doing something wrong. Needless to say, I'm at my wits end here, any suggestions would be a great help. Thanks

Try mist coats. Build up very thin coats. I only use Tamiya clear rattlecans (TS13, I think).
Also make sure if you've used decal softeners/solvents that they are absolutely dry. Bubbles can also be caused with some wetness still under the decals.

i've never had a problem over decals only CF when Tamiya melts them.