This is exactly what I needed from this thread:"Owner's manual, Page 38:
WATER TEMPERATURE: The economy heater water temperature is regualted by adjustment of the hot water intake valve under the hood. It is usually set fully open in the winter and fully closed in the summer.
TO HEAT: Pull out on the heater blower switch knob to open the fresh air intake. There is no advantage in intermediate postions.
DEFROSTING: The economy heater defroster control is a crank-type lever located on the heater-duct, under the instrument panel. Move the lever to direct the air flow.
FAN OR BLOWER: The three-position switch on the instrument panel labeled "HEAT" operates an electric blower located in the heater passage. With this swith in the center position, the blower is off. By turning the knob clockwise, two speeds are available."
Seems I need to buy an owners manual for the 67. I thought I knew everything about the 67-69 trucks, but I've learned something new!
Thanks for your help.
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