I replaced the water pump, radiator hoses, and bypassed the leaking heater for the time being. The old garden hose test on the radiator was positive, so I put it back in, for now. New fan belt, new spark plugs and wires (distributor cap looks like new), and new negative battery cable. Since it’s time to get the battery installed, I am now not sure what I have: a 6V or a 12V? Somehow, somewhere, or someone, I got the idea that I had the 6V, but after some clean-up (again, note that I said "some" clean-up) of the engine compartment, I can clearly see a "12V" on the tag of my AutoLite starter motor.
Getting close enough to a first trial start that I can almost taste it!