What to do with outside of new gas tank

I left mine as is on the truck when I put the over size tank in. Specta coats all their tanks inside and out with a special coating that resists corrosion. It's also very slick and makes coating them with anything else problematic, unless you scuff the finish. I had mine coated with Red Kote in the inside and it didn't stick. I had to remove it and have it cleaned out to get all the Red Kote out. It was a mess.