From my experience servicing these hubs, it's really not necessary to take the thing apart. Dump WD40 or similar solvent into the oil port, spin the thing around and let it sit a few days for the solvent to evaporate (keep the oil port open). Add enough oil till everything seems well-covered inside.

If you want to take the thing apart and really clean every piece, just soak any metal parts in mineral spirits or something similar (dishwashing detergent in water works alright, too). Just make sure the parts dry out before you put the hub all back together. Probably the most gunk will just be inside the hub shell itself.