questions about plasti dip

I recently acquired an old plastic gas tank that may have come from an old dirtbike or moped. I'm not crazy about orange, so I decided to plasti dip it black because paint will just bubble up. First question, it's roughly a 1 gallon tank, will an amount of plasti dip that covers 5 sq ft be enough? Secondly can I roll it on, and will it come out with a smooth finish, or do I need to buff it afterwards?

 

Bump

 

Well, nevermind about plasti dip. I found out its not fuel proof. Even a drop can cause it to smear, and the thicker you coat it, the more it smears. So I researched truck bed liner spray, and that stuff actually is fuel proof, so I intend to use that instead.