K frame refinishing and rebuild advice

Yeah, you can brush on POR if you want, that's what I did. They have started to make it in aerosol cans too I believe, but the brush on is the most common. It levels out okay for me, but I think a lot of that may have to do with prep work. Admittedly I didn't do as much to mine, just a wire wheel on a drill and then a wipe down with thinner before painting. A full sandblast would probably give a nice finish. I always have my black engine enamel as a standby though, lol. I've painted all sorts of stuff with that and it has held up pretty well.