i just wash it myself ....
must be done when engine is cold
1) use selleys degreaser ...spray on the area which have oil stains ..leave it for 2 minutes and run down with tap water with low pressure
2) soap it with meguire's car wash shampoo ..wipe it dry and after 5 minutes start the engine and let it idle for another 5 minutes or so
3) detailed it with CD2 engine detailer ...spray on and leave it to dry overnight ( the last step )
note : use plastic bag to close up the MAF , hid balast , air filter box , fuse box etc etc and pls use running tap water without pressure ...
work completed in 1.5 hours