When dealing with the brake discs, either new or tidying up old ones, I like to paint the whole disc in spray-on BBQ paint. I fint silver best as it seems to be thicker than the black and is cheap as chips on ebay.
The first time you use the brakes the paint will come off on the contact areas but stay on the other areas, stops the edge and cooling fins from rusting up. It also works on the callipers and I find it much easier than calliper paint.
Looks so much better for very little effort.
Barbecue, chips! Making me feel hungry Steve!
Going to order some silver bbq paint on eBay now so I do not forget the idea.