Yes I've done a few
Preparation is the first point, you'll need to get off all the rust which looks like it's been caused by Alloy Wheel cleaner, nasty corrosive stuff
Secondly and most importantly, you need two pack epoxy brake caliper paint. I tried every other type and it's the only type that lasts longer than few months
It has a tin of coloured pigment which you mix with a hardening resign. This normally goes hard in approx 30 minutes depending on weather conditions. So you'll need all the calipers ready and prepped before you mix the paint.
Halfrauds have stopped selling it because it's about £18 - £20 a can, so you'll have to go to a Chav shop which is always a laugh