Re:
I’ve seen u.v protection on outside of some rattlecans from carbody suppliers which are usually a better quality than Halfords etc but it’s still only going to be cellulose spray and struggle to see it having genuine u.v protection ,old decals were often very thin and not vinyl like almost all from past 20 yrs ,rattlecans often worst for solvent as paint needs to be v v thin to be powered by the aerosol,2k is still thinned down but compresser gives the ‘oomph’ to get spray out ,you might get away whichever you use if you let the initial coats dry before doing the next and certainly let the first cpl be v light ,they will dry and leave a ‘skin’ over the decals ,only try and get a ‘wet’ finish with much later coats once the first few have dried ,heavy coats can lead to the ‘pickling up ‘of edge of decals ,I would think rattle can are over 50% solvent ,if you have one near you it’s worth going in to talk to a proper car body materials supplier [the kind that knock up paints for the trade]