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My heater core on my 37 "120" is "shot" and beyond repair. I'm not going to replace the heater core and several people mentioned to just connect the fitting at the water pump to the heater shut off valve between #7 and #8 cylinder. I would think this would improve flow at the back of the engine? Wanted to get other opinions on this or should I just install a couple pipe plugs and seal it up?

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If you connect the ports together in a closed loop then I would suggest you use the shut off valve to restrict the flow quite a bit or use some other restriction. If wide open with a large flow thru the short loop a considerable amount of coolant will never completely circulate thru the engine and will bypass the radiator which could lead to overheating.

Ok, I was thinking about that also, I have the heater shut off valve wide open as seen in the picture, I think 2-3 turns open would be fine? I'm thinking this is a good idea to get more coolant to the rear 2 cylinders as I've been told they don't get enough flow back there? I did install a new water distribution tube, maybe I'm just over thinking again!

I would just close it. As it's not going through the radiator anyway, I doubt it would do anything to the rear block cooling and the coolant being bypassed would be of better use in actual cooling system.

If you put pipe plugs in the engine will look correct for a non-heater car and less cluttered.

If you are not using the heater, plug the hose connection at the water pump end and turn off the heater valve on the cylinder head. I'd leave the parts in place to avoid possible problems with corroded thread connections at the head and water pump and possibly losing track of the parts. The heater circuit bypasses the car's radiator to provide heat to the cabin. Simply connecting the water pump's heater connection to the heater valve in the cylinder head will reduce the cooling system's capacity considerably. This is not a problem in cold weather with the heater in operation, but it can cause problems in warmer weather with the heater unit removed. I know of a case involving a 1958 Ford 6 cylinder station wagon that had a chronic overheating problem. "Experts" cleaned the radiator, removed the thermostat, replaced the thermostat, installed a new radiator, and more, all without eliminating the problem. In warm weather on extended drives, the engine would slowly but surely get hotter and hotter until the car had to be stopped and allowed to cool off. The problem was finally solved when someone removed the hose bypassing the heater, which allowed the water pump to move all the coolant through the radiator instead of bypassing a significant portion through a short length of heater hose. If your car has a functional heater, it's best to close the heater valve in warmer weather to allow all the coolant to pass through the radiator rather than have any portion of it diverted through the heater, let alone a bypass hose. Unless your radiator is severely clogged, it will do a much better job of getting rid of heat than will the heater, especially if the heater is not in operation.

On the '37 120, hot coolant flows from the cylinder head through the heater core and then to the water pump inlet, bypassing the radiator. Thus, it is best to shut off the heater circuit in warm weather for the best cooling system performance. As for uneven cooling of the rearmost cylinders, that is not an issue with a properly functioning water distribution tube in place. There is no good reason to connect a bypass hose in place of the heater, and several good reasons not to do so. The system will work best as designed, with a proper thermostat in place. It was a common practice to open the heater valve in winter, and close it in summer, if the car had a heater at all.

Thanks everyone for the good advice, I'm going to plug it at the water pump and close the heater shut off valve.