I think the wrapping causing rust thing started with the older style header wraps being fiberglass based and the instructions had you soaking them in water to make them plyable, with the idea that running them after would boil off the water.

I picked up a little some DEI header wrap that I'm trying on a set of headers that are already a little beat up. It's supposed to be based on some kind of woven lava rock material and you're not supposed to wet it for installation. I'll try it and see how it does. I only really bough enough to do the visible tube area of the tops of the headers because this area was looking kinda rough and multiple layers of paint peeling on mine.

But yes I agree that ceramic coating would be the best option.