I have searched and found one post where it was stated that changing the plugs was "not an easy" job. Is there a special tool needed/helpful for pulling the wire cap off the plugs?

Are there any other special tools available that make working in such a confined space easier?

I don't know if it's needed on your engine but on the W210 E320 there is a 17mm valve adj wrench which is perfect for prying off/on the spark plug boots without damaging coil wires. MB Part No. 110-589-01-01-00 (Hazet 2771).

I've changed the 16 plugs on the M113 engine and detailed it with pictures of the tools that make life easier when you R&R the plugs. Please see http://www.benzworld.org/forums/r129...ml#post3504282