Finally got my timing cover off today. There are some very light marks on the inside of the timing cover from the cam bolts touching it occasionally. I think the biggest problem is the slop in the chain, way more that it should be from only 200 passes. I'm sure the front/back movement contributed to the wear. For the most part the cam is pulled to the rear by the distributor gear resistance. All that being said, it'll have a cam button from now on!