sludged up 2000 S500 engine pictures

[engatwork]

I had a 2000 S500 in the shop today that needed a new valve cover gasket. This is what I found when I pulled the cover. This is, by far, the worst sludged up engine that I have ever come up on.

The only way I know to clean it out would be to do 3000 mile oil changes for a year or so using Mobile 1. Anyone know of another way without taking the engine apart? I suspect that the owner is going by the oil change service indication using conventional motor oil.