Ceramic coating - Rust removal

[J_C]

Hi there. I've got some seriously gnarly rusting going on on the outside of my headers. They don't feel like they're weak, and there's no holes. I attached a picture.


I am planning on doing something like jet hot to the headers and cans as a part of my restoration project. (I really want to keep the 4-2 setup). I'm not sure if they or other companies sand blast the old chrome off before coating... if so would that ne enough to remove the rust? Or should I go at it with a steel brush wheel in advance? Thanks!