I can only comment on American cleaning products from experience, but maybe you can find similar ones.
Simple Green is a good thing to use to scrub gently with a brush. If there is too much cigarette tar, then Super Clean (purple stuff) is very effective and will make it all drip off. Use gloves, especially with Super Clean.
Afterwards, plenty of water rinsing with a hose, followed by spraying Isopropanol thoroughly in the windings, connectors, and all small areas to eject water that may reside.