Replacing a 3 wire defrost thermostat

I need to replace the defrost thermostat on my Amana side by side.
However, it is a 3 wire thermostat. The new thermostats available are 2 wire. What is the correct wiring procedure for retrofitting in the new thermostat?

Never mind, I am mistaken. I looked at the thermostat wrong. It is a two wire, but the wires were tied up with the heating element and looked like three wires. Sorry for the confusion. Easy replacement.