A very thin layer of Ultra Copper on the timing cover and teflon pipe dope on the wet bolts. On any of the long bolts that go through the timing cover into the block I like to use a thin layer of anti-seize on the shanks of the of the bolts. It can save a lot of headache down the road. For the china walls, I sue the same silicone and let it dry for at least two days before trimming the excess with a razor blade.