You said you no radiator fluid is spilling out but have you noticed less in the radiator? If so, you might want to check the oil to see if it looks foamy or cappucino like. Probably unlikely, but maybe the head gasket isn't sealed properly on the new rebuild and radiator fluid is in the oil. It's probably something mentioned above but you might want to check that too.
"An ignorant man thinks he knows everything, a wise man knows he doesn't."
