I'm having to replace a corroded side-mount gas tank on a 96 F250, along with the vapor line. I'm ready to install the new tank, but feel like I need to coat it(and the strap hangers) with something to prevent having to do the same job again a few years hence. I'm a little pressed for time and am thinking of using rubberized undercoating, since I'm thinking it dries pretty fast. Am I correct? What would you do?

Thanks as always, friends, for your time.
Andy