oil leak

[saujad]

I have an odd oil leak and am hoping someone can give me a clue on how to find where it is coming from. I have a 83 300sd.
The leak is above the starter in the area of the cylinder head. I am unable to see were the leak is coming from because of the intake and exhaust manifolds are in the way.
I have already replaced the valve cover gasket which was no help in stopping the leak. I don't know if there is a cylinder plug or something else in this area.
It is a bad flow of oil, leaves about a fist size of oil spot on the ground every night.