Someone has taken the gas tank off, and used gasoline in the Kerosene tank as the fuel. Look on the bottom of the fuel tank, there may still be part of the kerosene shunt still there, or a plug in the sediment bowl body. That was pretty common, especially in areas where gasoline was cheap, or more available. All of your model of tractors could use gasoline, or start with gasoline and switch to kerosene, or distillate. The part number for your missing tank is AS-843.
Take care!!
Andy