My new gas tank said it had some sort of rust protectant on the outside. The stated they recommend not painting it.

Should I still clear coat it to help make it easier to paint or just leave as natural?

If I recall they protect the tank with galvanized steel. And if it is the paint will not stick unless there is a new prep procedure to allow it to stick. But galvanized steel wont rust but may corrode over time. And grinding the coating off will create a poisonous atmosphere as you grind away. If I'm incorrect I hope someone corrects me.

This is a tread on the topic from last year . https://firstgenfirebird.org/forums/ubbthreads.php?ubb=showflat&Number=264142&page=1

Here was the tanks specs.

O.E.M. approved ni terne steel
Corrosion resistant

The tank had already started getting spotty so I decided to clean it good and clear coat it.
Hopefully it will hold up.

What about powder coating