Mack,
follow the hydraulic lines to there destination. That will give you an idea what you are dealing with. The 3126 has a HEUI pump for the injectors, but I believe it is located more topside on your motor. From your picture, looks like the hydraulic pump for the power steering. If you can power wash the oil off, then start coach, you may be able to locate where leak is coming from. It may be a pinhole leak in one of the hydraulic lines. Any hydraulic shop can make up a new hydraulic line. Hope this helps.