Haven't done this one myself yet, but here's a link to someone who has. Read the reply by pmizell where he details pretty much a step-by-step of the procedure, as well as a list of needed tools, parts and supplies.

http://www.peachparts.com/shopforum/showthread.php?threadid=79978&highlight=front+cover+seal


This link shows a diagram with the likely suspects circled:

http://www.peachparts.com/shopforum/showthread.php?threadid=77204&highlight=m103+front+engine+cover

For more discussions, do a search on "front cover seal", "front engine cover", "upper timing chain cover" or similar.

Gary