Got the thermostat and the restrictor plate in my 1972 Ranchero today,installed a 3 row aluminum radiator,new hoses,thermostat housing,shroud and flex fan,timed her,adjusted carb, 3 gallons of Be Cool anti freeze and a bottle of water wetter she is running at about 183 degrees now,it is fantastic Thanks! Drilled 2 small holes in the thermostat 2 to bleed air and such too.
Bought a fluke 62 MAX that was on sale and read all the temps from the headers to the alternator temp,the water pump was reading 145 I couldn't believe it!
8k on the motor and she seemed to be running hot to me, popped the thermostat housing and as any 351C guy knows you have to have the brass restrictor and the correct thermostat he had the wrong thermostat,the radiator had about 1/3 of the rows plugged it was a 4 row copper. Got the aluminum on sale from ebay was "not" direct fit like he said but 3hrs plus of tweaking and we are good to go not bad for $180 bucks!