Have a look at the link below. When I initially looked at this engine prior to pulling it apart, it looked like the OFHG was leaking. It was only after digging a little deeper that I found that this was not the case, it was the oil separator. The tell tale waffle iron spot can get oil from either the OFH or the oil separator. Scroll down and have a look at the pictures, and you will see what I mean. This may be your problem.