Hi - Not sure how many of you already do this, but whenever I have a bolt head that needs painting and I do not have the time to wait for the paint to cure before installing the bolt I will just remove the bolt, stab it through a small piece of newspaper, and then re-install it. This acts a shield for either a brush job or a rattle can job when you want to avoid overspray. I then tear away the newspaper when finished. There may be a small leftover bit you need to cut away with an exact-o knife but generally it all comes off the first time if the paper is wet with paint.
Any other tricks out there that you do?
Scott