My first thought is that you need to purchase a good manual if you are going to attempt repairs. I think even a Haynes manual covers this with some pretty good pics.
Front wheel bearings are normally a good diyer job but understand that the way you tighten MB wheel brgs is a little different. If you pull the cover off of the hub (the special tool is a screwdriver and a rubber headed hammer) you should go ahead and do the brgs. The difference in the MB wheel brgs is that you have to make sure you put the proper amount of grease in there and you have to make sure you tighten the nut to the proper tightness prior to fastening it down. Even if you go with new wheel brgs the relatively inexpensive.