Why you might ask.... well those famous words "the customer brought it to me" and there's a couple more 5' by 10' billboards he needs done. He bought these from a retired sign painter. I will go with 1-shot if I have to but for speed of drying & it not chalking I prefer latex anymore, and these are to be brown. Anyone done this and had lasting results. I'm in PA. When I see some of the ones I have to re-paint, I'm pretty sure the fella used an enamel...I want to use vinyl lettering & hate the wait for enamel to cure.Any thoughts, thanks, Robin