New Gas Tank Question

I have a new gas tank for my 64 Barracuda. Ni-Terne plated, whatever that is(guessing a kind of galvanizing???)

Now my question. The underside of the car is coated in what appears to be the same black stuff that my son's spray in bed liner consists of.

Should I coat the gas tank in something similar to ward off rusting, or just prime it and paint it, or just leave it as is??

What is best for the tank longevity??

Thanks

FF