I also use the anti-freeze/crockpot method. I leave my engine in overnight on low heat. I've heard high heat will discolor the aluminum. Disassemble the engine as far as your comfortable doing, minimum, remove backplate, carb, and glow plug. Use an old toothbrush to loosen any crud left when you pull it out of the anti-freeze. I use air tool oil to lubricate after rinsing and drying the engine. I use Marvel Mystery oil as a after run oil, but if you store an engine with it, it will coagulate, making it difficult to turn over.