Hi Damascus, I've got thermometers that go high enough, it's finding a heat source that's more controllable than my ye olde camping stove that I'm looking in to.
It's mainly to save time (if possible) while still getting every part the same shade of blue. It's one of the little jobs that I really enjoy but can easily turn into half a day if I don't keep my eye on the ball and go too hot.
Thank you for the suggestion though.

Rust never sleeps !