I did the conversion on my 90' 300CE about a year ago, I have been very pleased. Incredible difference from the US lights. I also installed the clear turn signal lens. Found that if you get the wiper motors and arms from a 95 E320 they worked perfectly with the Euro headlight kit. Mostly just plug and play the wires and installation is the same as the original wiper motors. Looks great as well as functional. Interested in a Zenon kit but have found them to be a little expensive, and not sure if they work with the Euro lights or if they replace them.
Great Site. Been an onlooker for a while now, thought I would put in my 2cents.