how difficult is it to replace the valve cover gaskets on a 2001 Audi A6 2.7L on 2001 Audi A6 Quattro

i recently purchased the car and it was a one owner car that had been well taken care of. I noticed the smell before I saw the trace of white smoke coming from the engine. There is no trace of oil under the car where it sits so it leads me to believe that it only leaks when its running. the car has 118,000 miles on it and it recently had a major service, timing belt, serpentine belt, both coolant pumps, and plugs.

Asked by for the 2001 Audi A6 Quattro
Here's a video to show you what is involved....It's a pretty serious undertaking: