Any tips on replacing the circular camshaft adjuster seal? Not the half moon piece but the 2" donut looking seal. I can't seem to find out where the seal is.

BTW, here's pics of my engine once I had the valve cover removed. The engine block looks clean but the underside of the valve cover looks filthy. Since the engine block looks clean, does it validate that I shouldn't worry about oil sludge right now?

TIA!

http://i260.photobucket.com/albums/i...r/IMG_0139.jpg
http://i260.photobucket.com/albums/i...r/IMG_0140.jpg

 

Asked an Audi mechanic and he said that it's a PITA so don't even bother since timing belt would have to be removed. However, I did attempt to replace the half moon seal for the Camshaft Tensioner and even had the tool to compress the tensioner but it was still too difficult since I was only able to get a tiny little bit of slack loose from the chain.