Thanks for the reply chowpit and Benzmac. The valve seals comes as no big surprise since I was aware of other people on this bourd having had the same problem. I'll be calling 2 MB dealerships and a couple of indipendants for pricing and sheduling.
Benzmac, since you've done many, many valve jobs in the past what dollar range am I looking at to replace the seals on all 12 valves?
Cheers for now