What kind of clear coat should I use on my box? What do you use?

[maylar 10+ year member]

Again, the most compatible clear will be the same brand and product line as the paint. You will have to scuff the paint with a grey Scotch pad (abrasive mesh) or 600 grit wet to get adhesion. Two wet coats and call it done. If you layer clear on too thick it'll have a tendency to crack or craze.

Don't over think this - it ain't rocket science.

 

[honkyg 10+ year member]

id just as soon roll clear fiberglass epoxy resin with a foam roller all over it in terms of finish and durability