WD-40 is actually slightly corrosive...

I would advise against soaking in Glo fuel, as it's hydroscopic (attracts water) so, you never really get it [water] all out, and you'll eventually get some rustiing. Not to mention the cost! Use regular gasoline, or kerosine. Just do it outside / in a well ventilated area! Don't use Acetone, as it'll eat away at the aluminum.

The best I've found / been told, is to dissassembly the engine as best / much as you can, and dunk the parts in Ethyl Glycol (Antifreeze) which is lightly heated in a crock pot (Don't use teh crock pot after this though!!!). Submerse them parts for a few hours, like, over night! Don't do the plastic parts and rubber O-Rings thogh, as the antifreeze will likely distort them. Tooth brush and some soap is best..

Pull them out, rinse with warm water and let dry. Warming them up (oven on low for a few minutes) garuantees the water evaporates. When re-assembling the engine, use a light machine oil. Be generouse on the bearings!

Wrap the engine up, bag it, and add one of those dessicant packets ( the little 'Do not eat' packets you get with electronics) to the bag, and seal it up!