95 e320 o2 sensor wiring under floor mat...

[zakatekaluka]

I am generally an 80's w123 diesel owner, but could not pass up a great deal on a 1995 e320 wagon, even though we were told it "has issues". Ticking them off the list one by one and I'm to the o2 sensor. I read that the front o2 sensor is wired under the passenger's floor mat, and that a good first step is to simply look and make sure the connection is sound. I removed the floor mat and...well...things aren't pretty down there.

Below are some pics. Is the cruddy horrid mess in the red circle the connection I'm looking for? Or is it hidden under the case with the other wires that I've put a green rectangle around *crosses fingers for that option*?

And then...if it is that crud covered monstrosity... That would probably be my very first bet for getting o2 codes. Can that be cleaned? And if so, with what?

Thanks for any answers you can give!