I have several touch ups I'm going to be doing on my Baywatch cabinet. As I will be using an airbrush and only touching up in spots, I was thinking the final sheen may be a bit off, so I will need to put a clear coat over the whole cabinet. I would think this would be good for further protection as well. So ultimately the question is, what clear are most using for this purpose? I'm assuming a satin/semi-gloss, but wouldn't want to use a spar urethane, or anything of that sort as it yellows over time. Thoughts?