If indeed it is a ‘70s 250 I-6 put EVERYTHING back exactly as it was delivered from the factory. Make sure everything that is supposed to be open is open and everything that is supposed to be closed is closed. All filters in place all valves in place. If it still blows oil you are looking at a worn out engine.
As Buoymaker pointed out, you basically posted this same question before. Posting the same question multiple times hoping for a different response is not good forum etiquette.