1998 Lincoln Town Car heater core motor post broken

When I bought the lincoln, I did not notice that the hoses to the heater core had been bypassed by looping a short hose between what I will call (for lack of exact terminology) the intake and output post on the back of motor. While driving, car ran hot, I pulled over and noticed complete loss of coolant. After pouring water through overfill-noted location of leak. Was finally able to remove VERY short hose used as a bypass and the hose was OK. Ran more water through and was very alarmed to see (cramped small area) that the bottom post to which the hose had been clamped was barely attached and the water was pouring out the area to which it should have been attached. (It looks like the hose had been too short and was under such pressure to connect at such extreme angles that the post had finally broken as the hose had tried to return to a more straight position.) My question is: can the intake and output post on the motor be somehow plugged without compromising the circulation of the coolant through all vital parts of the motor? If so, any suggestions as to how this might be accomplished on the lower one, as the post broke off at less than 1/4" from the motor (nothing to connect to)? Desperately need the vehicle, but no worries about the heater!