5X5 Fence Post Mod - Length Question

Sifter, I used a clear coat for a primer and the just some Rustoleum paint that's for outdoor plastic patio furniture. I 1st took the sheen off with a scratch pad then sprayed the clear on. It acts as a primer. The clear bonds better than the paint. Follow that with your color of choice. I used to race remote control cars when younger and I would buy different bodies for the cars. They were clear and needed painting. We always painted the clear bodies on the inside with clear to help adhesion. So I just applied the same theory to my fence post.