I used a one piece Felpro Permadry Plus blue oil pan gasket (part # OS34509T) on my new 350. Now I have a big rear oil leak. Has anyone ever used this gasket and if so how did it work for you? It seems like it would work great being a one piece silicone rubber. I put sealer on the 4 edges of the pan like the directions said to do. Not really sure if it's the pan or the rear main seal yet but have never used this gasket before. Is it any good? Thanks.