What cleaners do you use? I know Cali limits what can be bought due to hippies, but over in TX we use B-12 Chemtool that stuff instantly removes oil and grease without scrubbing, then I take two pipe cleaners and spray while moving the pipe cleaners inside the oiling holes, then use compressed air to clean everything out that might still be trapped in there. Gotta use the pipe cleaners man inside the holes. They are fuzzy and the bristles don't come off easily... they look like this.
http://thesmallobject.com/stenopad/wordpress/wp-content/uploads/2008/10/MAKE%20trim%20pipe%20cleaners.jpg
http://thesmallobject.com/stenopad/wordpress/wp-content/uploads/2008/10/MAKE%20trim%20pipe%20cleaners.jpg