Sounds good man, you are taking a litttle different approach with your cooling than I did. Since mine was a side by side and I cut divider out my freezer never really gets very cold, esp. with all the air circulation. Just remember that the design of your fridge is to keep most of the cold air in the freezer. Did your test ever reach the point where the refrigerator cut off? With temps in the minus range in the freezer you will have a lot of residual cooling in your box. I would suggest seeing what happens to temps after fridge cuts off. My fridge thermostat would not let me set the temps. warm enough so I had to replace mine with one from an A/C. Dont know if you know it or not but there is most likely a defrost thermostat on your fridge that will turn off everything in the fridge and turn on the defrost heater at least once in a 24 hr. cycle, you are gonna want to circumvent this.