Has anyone replaced their valve cover grommets? These are the washer that fit into the top of the valve covers. These grommets have dried out and cracked. I found some that were listed for the 3.0 dohc that fit into the cover but they are flush to the top of the cover and don't allow the bolt to compress them without the bolt bottoming out. Has anyone run across this problem and have any suggestions for a fix? Thanks.