I think if you take the intake off and its dry the next step is to pull the heads and see if its a head gasket issue. If its neither of those then it has to be rings. Again sorry about your engine.
I believe it is the intake gaskets leaking. I'm not fond of the steel ones I used like above in the pictures that I posted. Composite would have been better.
I have made up my mind and going to find a 360 because the lil 273 will never be the torque monster I want. So I'm not going to invest anymore time and money in the 273 until I start to pull the motor. LOL!