Alloy wheel touch up paint

[Al182]

Hi all, I've got a 182 with the standard anthracite alloys. The paint has come of in a few places and it really isn't a good look. I heard that a good paint match was Rover stone grey from Halfords. Just wanted some tips on how to apply it to get the best finish. I imagine that once you've applied both the primer and the paint it would be pretty obvious and uneaven. Any one got any experience touching up their alloys.

Thanks.