You can also use something like this.. you can really control how much you fill the chip..
You will have to play with thinning the paint so it flows through the pen well..
I cant find it now, but I also have a pen like tool which is a bundle of glass fibers, which is greats for cleaning out, and giving some surface prep within the chip
Comes with a little reamer to clean the tip.. I have a few of these, you can get different diameters as well
