How to replace a foamed in thermistor (hoover fridge)

Background:
I have a Hoover HNMF 2805A fridge freezer that is constantly cooling, thus freezing everything in my fridge. I have bought and fitted a new PCB, and tried to completely defrost the appliance, but the problem remains so the temperature sensor must be faulty.

Having browsed this forum, it seems that I need to cut out a piece of insulation at the back of the fridge, fit the new thermistor and seal it back in with a bit of foam. I just wanted to ask if I have the right idea before I try it.

Is this how to change a thermistor?:
– Allow appliance to warm to room temperature.
– Remove doors and unscrew metal case.
– Prop coils against a wall (there are two tubes in the bottom right corner and I am worried about breaking these if I allow the coils to move too far from their operating position.)
– Use a knife to extract thermistor, working in the gap between the coils and main unit.
– Feed thermistor cable through cable conduit and attach to PCB.
– Refoam, reassemble.

Or am I supposed to access the thermistor from the front?