valve lifter cover

I've had a leak on my 235 valve lifter cover. I ended up putting a rubber "Real Gasket" on this weekend, and there was still a small leak. I had tried to flatten out the dimples at the sometime over tightened bolts. Our friend Dragsix provided another cover which is in much better shape than my...

I've had an oil leak at the valve lifter cover on my 235. Here are some photos. The cover is not warped, and the flange on the engine is flat. Could it be that the indentations at the bolt attachments are the problem? Are those indentations suppose to be there? Perhaps overtightening the bolts...