Just my .02 but I would use a brushable paint on the calipers. Less worry about overspray, you don't have to tape off as much, and you can definitely leave them on the car when you do it. Just head down to Wally World or Home Depot, and pick up a can of Rustoleum enamel in your favorite JDM yellow and paint away. Its how I did mine (black that is).
I took my drums when I sprayed them.
on your drums by the way.