where is defrost thermostat located

i need to install a defrost thermostat ,defrost timer kit and a radiant heater on my admiral but can’t find them i need help please

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Behind the back cover in the freezer is the evaporator coils. The heater is under it or woven thru it. the defrost thermostat is clamped to the coil near the top. The timer could be behind the kick plate at the bottom or in the fridge control area.

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