Any suggestions for cleaning the engine?

[ToddEdge]

I'm picking up an '06 on Wednesday and when i looked it over prior to purchase, I noticed the engine/plastics under-hood were all very dirty. This is the first diesel I've had in 15 years and apologies for the newbie question... any issues spraying everything with engine de-greaser and rinsing with water? Any areas to try and avoid?

Thanks - Todd