Of the few that I have done. I use VM & P Naphtha on q-tips. Pour a small amount in a glass jar with lid (jam jar ?) Paper towel off the excess from q-tip. It works great on the donut part that seems to attract a lot of greasy muck. Also can be used on the sides with the fine wires, carefully of course. Any areas that can't seem to be reached with the wide head of a q-tip, get some small artists paint brushes. i might use upwards of 50 q-tips on one flyback. Any fine fibers left from the q-tips can be pulled off with tweezers.
Just my 2 cents...
Tony
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