M-B have a special high temperature anti-friction bearing grease that's packaged in the right amount for the two front wheels. The part number used to be 001 989 23 51 10.
M-B wheel bearings generally don't need to be repacked until you replace the rotors (90K?).
Another thing that can be used to clean wheel bearings is diesel fuel but it stinks if you get it on you.
The way to adjust play is with a dial guage unless you are highly experienced with these cars.