I would venture to say that if it is the headgasket, it is because you did not remove the rivet.. I just put a Titan/cometic into mine as well and had to remove the rivet. Some of the newer ones are rumored to clear, but I did it anyway to be sure. Also, another great test to check for BHG is a block test... I'm sure you know what this is, you can pick it up the fluid at NAPA and rent the tester from auto zone any time you need it.