Sparkplugs: BOSCH F7-KTCR.
They are triple electrode plugs and no need to adjust the gap on them.
Just install them " out of the box ".
M-B plugwires do not have any resistance, their are resistors build into the connectors.
A little bit of oil pooling around the plughole is okay.
If you ever get a lot, you can replace the 4 "O" rings in the valvecover gasket .

http://img.eautopartscatalog.com/live/A802937397GOE.JPG

http://img.eautopartscatalog.com/live/F1000184876BOS.JPG

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2007 C 230 Sport.