I removed the manifold (and destroyed the new gasket in the process-my luck) and there doesn't appear to be any cracks in the head. On way to go pick up new gasket at O'Reilly's so I'll pick up some Great Stuff or whatever I can find there. I only have pipe thread sealant and hi-temp RTV at the house. I used pipe thread sealant on the other corners but they seem to be holding up well! I wonder if I should reseal those or leave well enough alone?