dust cover holes - - yep - just for holding the dust cover - there may have been a brace (I can't for the life of me remember if it was on the left or right side) that attached to the one on the right - but most people don't reuse it. Just put some bolts in there and move on. Your valve cover is likely on the wrong side - I had to mount mine so the breather is to the right and the PCV is to the left.