Man mine started as a valve cover gasket, then when I went to change it I noticed a bit of milky oil on the rockers, pulled the head and realized the #2 fuel injector was not spraying well or at all. The Jeep never ran bad enough to notice it, it just ran like a Jeep but the spark plug ended up melting the side of the piston. Wow did it run much better after all that fun!!! I feel the pain........

 

The head is cracked, i wouldnt get it checked just get another head and check that one. Hopefully you caught this before you did bearing damage.

 

Might be good to run a compression test on your cylinders, and if you take the head off check for bad water jackets.