I put some on heavily and let it soak then I too use a tooth brush to scrub and clean. I do this around all caps as well. You will want to rinse well, vinegar is acidic. So I use warm water, a few drops of dish soap and a paint brush to scrub the entire board. You will want to remove socketed chips (photograph first). Then I use a hair dryer for initial water removal followed by a space heater to dry completely. I occasionally blow into the ports/PDS slot to get any water out then back in front of the heater. If you have hard water, you will have to use distilled water for rinsing instead. This is my method, there are others of course.