Andy's Dog House is working on a 1954 Dodge Fargo 1/2 ton

Submitted to Product Chat

I am restoring a 1954 Dodge Fargo 1/2 ton. I want to paint it flat black. 
I would like to know if I used Rust-Oleum paint, will it fade or discolour after a few years.
Does Rust-Oleum paint need a hardener if I use it on my truck?
I've seen others using Rust-oleum paint on vehicles on YouTube, but nobody has ever said how long it will stand up and look good.
Thanks
Andy