I just used Varsol (mineral spirits). Cheap and works just fine. Dunk the parts, swish em around and/or use a paint brush on them. Then dry off and reassemble. Keep the plastic powder hopper out of the solvent. The funnel at the bottom of the hopper is the hardest spot to get without a spray degreaser. I just used a clean rag for that.
If you're stuck on spray degreaser, ether (starting fluid) works pretty well too. It's available at any auto supply store. It is HIGHLY flammable though (almost explosive with the right fuel/air ratio), so use it outdoors in a very well ventilated area. If it's not breezy, give it a little time to dissipate between sprays.
