C300 oil drain plug

C300 oil drain plug

Hi,

I have an '09 C300, and have been doing my own oil changes using the "extraction" method.  I've not been satisfied with the amount of oil I get out of the engine - I am getting 6 qts out, and engine holds 8.

So, I want to start using the drain plug under the engine. I know this is a stupid question but here goes: I pulled the plastic cover off the underside, but I am in doubt as to where the drain plug is.  There is black 3X6 panel and what appears to be the drain plug close to the panel, on the drivers side of the engine.  The black panel is what is confusing to me - every oil pan I have ever seen is a solid piece of metal.  

Have I located the drain plug or is it another location?

Thanks, I appreciate your patience.      Dave Spry