Zeev, the site I mentioned is the American Truck Historical Society's forum, they have a technical questions forum here: http://forums.aths.org/InstantForum414/Forum14-1.aspx if you go through the pages, you will see how people are trying to help each other and there are a couple of members who have worked on Cummins/Fuller/Rockwell for years and really know what they talk about. From my experience someone will have an answer to your questions
Also useful is the "Parts and Services" page: http://forums.aths.org/Instantforum414/Forum15.aspx - lots of places where you can get what you need directly.
Joining the forum is free, yes, you need to know English but not a professor's English, the people on the forum are "normal" everyday people, many are old truck drivers and nobody expects you to be perfect with you English... T
PS: The last picture is from http://147.237.72.31/topsrch/default.htm