I should wrap the header, but I won't do it... Yet. The paint is doing well so far. If it does get worse, then I'll just wrap the top half of the header. Im guess the temps arent really high is because I sprayed the exterior of the header too, with that same paint.
Good to know the longevity of this header is a decent one. That's why I chose this set up, not too expensive and it has pretty good history.