Best thing I find to use is Autoglym Engine and Machine Cleaner...

Start the engine, spray EMC everywhere you want to clean, aggitate it with a brush, then rinse off. Be careful not to drown all the electrics in water though. Then you can just wipe off the excess water. Then polish it if you want.

I love that gear, I clean everything with it, all under the kit and every little groove. I also clean my RC car the same way, start the engine, turn it on its side, and cover in ECM then rinse off with a hose