The cooling system connections are fully described in the video instruction tape. The water heading from the engine to the Radiator requires that you plumb from the "Goose neck" on the intake manifold to the water pipe under the left side frame rail. The water coming from the rad. to the Engine requires that you plumb from the right side water pipe to the Chevy Water Pump.
The water connections for the heater core are just as simple. You will recall that earlier we installed 2 heater hoses to the 2 Heater Core pipes. One of those hoses was 5/8" in Diameter, that hose handles water going to the heater core. You will want to connect that hose to the appropriate fitting on the Chevy intake manifold. (on TPI engines you will run the water coming from the engine thru the connections on the underside of the throttle plate before you let the water go forward to the heater core). The other heater hose is 3/4" Dia and it is routed to the appropriate fitting on the Chevy water pump. The video details the proper filling and bleeding of the cooling system. Simple as that.
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