Once most of the paint is off Using chemicals or media blast , an orbital sander quick once over then, start with thorough de grease and magic eraser. 320 wet dry and work your way up to 3000 or higher. don’t move up grits until all the big scratches are out. you’ll never get them out with the finer grits.
I also use a Dremel with a 1 inch hook and loop sanding mandrel available on aliexpress . This lets you focus on small areas, and helps getting into corners, and saves wear and tear on your finger tips too.
finish off with Flitz metal polish.
I’d post a pic, but never bothered to figure out this new board.
