Glow fuel works fine for oil and residue, but only to a point. Acetone works much better for dissolving the varnish I've found. The crockpot antifreeze trick works well, but it has to be heated and given at least 6-8hrs to do its best work. Most guys use the green Ethylene Glycol undiluted, but some have had success with the extended life types (propylene glycol). Either method will require complete removal of the solvent, drying, and oiling immediately.
Ive had great success with engine bearings from rcbearings.com and equal success using bearings from AvidRC.com as well. Avid is dirt cheap ($1 each) and seem to be identical in every way to what RCBearings sells (which are the same thing as Boca's econo bearing sets). If you use coupon code "shout" you get 5% off your order or "RCU" for 7% off your order at RCBearings.com.