Tusefe60xi

I was in the process of installing out my radiator fan and in trying to install in that clip on the right it broke the top of the Automatic Transmission Oil Cooler Thermostat part that connect to the house. It looks as if its the top is a clip but I can't find a part number for it.
Do I have to replace the whole Automatic Transmission Oil Cooler Thermostat unit or is that top clip replaceable?
Has anyone done it and what do I need to look out for other than draining the coolant.
Also would I only need to drain the coolant because I dont mind doing that I just dont want to end up having to drain the transmission fluid because thats difficult
Can anyone explain the steps needed to remove the thermostat
I know there is about 5to 6 t27 screws holding it down but im not sure what to do after unscrewing them
If there are any videos that would help that would be great

I have included some pictures to best describe what is going on

ALKada

You will have to replace the thermostat on this one. They are not that expensive and if you have not replaced it yet, now is a good time.