Having a hard time finding the right part. Have a 2008 CLK350, and the underbody panel that runs under the wheel well back to under the passenger feet.. is an odd shaped piece, but the fastner that joins it to the larger long panel under the passenger carriage and the under engine panel, am trying to find that screw/plug/panel fastner. Mine has fallen out (not sure how) and I can't find a part number to match to find the right one...

If someone has a blowup of the underbody panels and the associated parts, that diagram might help me find it... any thoughts?

So in researching, I came across this potential... but cannot find a diagram online (through mercedes or otherwise) showing if this is the right bolt/screw to hold it. The panel looks like it goes into the frame rail, which means putting a retainer clip behind it is near impossible (the panel prevents your hand from getting there:

Under cover screw 001-990-60-36

I just can't tell if that is the right one... and before I go to Home Depot and buy a short sheet metal bolt, that is about 3/8" in diameter and force it in there... would like to find the right part... any suggestions other than going to dealer, putting on rack and pointing?

Hey Monty3038,
There are two type of fasteners there (and one type of retaining clips):
Metal screws 001-990-60-36 (which you get right)
Retaining clips for those screws 004-994-31-45
Plastic washers 201-990-00-50

Interesting, am going to have to look these up and see what looks right or not... the screw doesn't look 'big' enough and also not sure how you get the retaining clip into that hole without having like microscopic fingers... going to have to look for them and a video on them... btw... thanks for the help.

Sure, here is couple of pictures

Retaining clip up close

More retaining clips

Plastic nuts

Hmm... found one more: second picture left most (circled in red) retaining clip is 001-994-98-45

So the one closer to the wheel is the exact spot I'm aiming at. Mine is missing... the problem is, there looks to be a frame rail or floor member above this, which has a small square opening, looks too small for the clip to enter... that is what I'm struggling with, how would I even get a clip in there? Or is that a plastic fastner that I just can't identify yet... thanks again for all of the help... frustrating how the parts blow ups don't show the bolts/clips/fastners with numbers... looks like a bolt on the drawing I found, but can find no reference to it.

That one should be 001-994-98-45.
https://www.google.com/search?q=0019...w=1858&bih=926

I think you simply need to insert it into the square hole.

Ordered... will let you know when they come in and if that fits... will try to remember to take pictures... Thanks!

Parts arrived. perfect fit. Thank you so much for the help!

Any time!