Get things covered up. Gloves on and fan cranking. Pre wipe as much as you can off the top. You want to keep gunk out of the segment. This one is not going to be too hard, as the typebars don't run downhill. Brush, blow, repeat. Swap out for clean brushes often. Time for the brass, And save the "you're going to damage the slugs" bs. A brass wheel will do nothing to the slugs except make your life easier. Inspect and time for the pick. Use your phone and take a pic. Inspect the vowels closely. Brush, blow and repeat. Are they clean? If you are looking at a FBM "professionally serviced machine," look those slugs over. If they can't clean the slugs, what can they do? Now you are ready to wipe each typebar with the solvent rag. Cleaning the slug under the typeface is the worst part of it. People will clean the typeface and let years of junk build up underneath. Now you are ready to tackle the segment.