Few things. First you need more glue. O relay the hic edge. Hide the seam.
Second you need to do the hic black before you do it silver. Needs to be jet black. That's what gives the silver depth.
Best black and silver paint is testers pactra. Indy silver and black.
I would use lacquer based paint. It sticks best.
Lastly for everyone. Clean it with alcohol very good. Will prevent the bubbling.
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And with lacquer you shouldn't need primers. I think though that auto stores sell black primer.
Really important don't mix lawyer acrylics and enamels. Will make for sticky good.