Order of assembly? From a bare shell

So Rustoleum is like hens teeth up here for whatever reason. Their undercoat is discontinued. I looked into different paints and Armor Coat has great reviews, reasonably priced and requires no primer.
I'm hoping to be able to topcoat it with Proform undercoat. Auto supply store called and the Proform cavity wax is in.
Hopefully tackle it this weekend.
Thanks for suggestions n advice guys.