replacing Plugs, in the rear wheel opening?
 

I was crawling around my 300 TD, and noticed that there is a rubber plug missing from the inner fender/splash panel on the rear. has any one ever replaced these, or others? I am guessing it is a dealer item, and will have to go there some time and order some other little bits

I dont want any more dirt of water getting caught in there. could it be flusheed out? as I see there is a drain hole about half way to the front of the car but I would like some one who has experience to say 'yes' or 'no' to such a procedure.