To answer your question directly, although the paint is solvent based it is actually an alkyd enamel product so will work well over the base you have laid down. Alkyd is a rather universal problem solver and sticks to most anything. Most anything can be painted over it as well. I would check for a manufacture or expiration date to be safe!
"1 Shot" is what most pro sign painters I know use. As you probably know it is designed for lettering, pinstriping and so forth and is nice because it will not "crawl" on you. It comes in a rainbow of colors and they mix well together to get just about anything in between. There are several green hues and I forget how many gold ones. Obviously the metallic color chart would be irrelevant on a computer screen so look in the store. You can get 1 Shot in small containers too which is nice.