Were you using OEM torque spec, or the headgasket manufacturer's torque spec? Sometimes headgasket makers specify more torque than an OEM gasket, especially if they're metal gaskets. Also, did you reuse the OEM headbolts? Those are supposed to be replaced if you pull the head. Other than that, are you sure the gasket is oriented correctly(not upside-down, backwards, etc)? If you think your block is warped, then it would need to be decked to seal properly, but since you've already shaved the head, that could yiled a higher c/r than you may want. It may also move your pistons dangerously close to your valves. Before changing anything, I would go ahead and retorque everything.