Looks like a low mount water pump 235. Either of the two on the water pump itself could be used for one hose to supply coolant to the heater. The return hose from the heater would connect at the thermostat housing. As far as which way to connect the hoses at the heater, I would use the uppermost connection and route that to the thermostat housing to assist with purging any air from the heater.


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.