I have recently pulled a EJ22 engine to swap into a 94 Legacy that threw the rod. I have removed EJ22 engines a few times on other 2.2L Subies, done timing belts, and it is a fairly simple process. My question is the engine I've found has several oil leaks which I would like to clear up before installing. One of the confusing ones is the Camshaft o-ring replacement. On the back of the engine (passengers side?) it seems like the oil is weeping out of the cover which is bolted down on the head. I understand there is an o-ring in here as well as one on the opposite head in front. Are these o-rings easy to replace and can I get some advise or a link into a string that goes over this? I can't find this process discussed in any depth within the forum.