What can be used as a diy topcoat for automotive 2k paint?

Answer
Go to any nice car paint distributors in your town or city and get a single pack lacquer, sprays straight from the tin no need for thinners or hardners and its excellent stuff. put a single drop coat on let it go tacky then wack 2 more coats on let go tacky then 2 more will look mint.take you using a spray gun and compressor to spray ?