Can't believe you did the clutch before the fan switch!
Fan switch is by far the most likely culprit, here it is circled in green, costs very little, let's hope that's what it is.
You can test it by pulling the plug off the top, and then shorting the 2 pins (female pin holes) on the plug. This is all that the fan switch does, gets to a certain heat then shorts the pins. Should come in at a little over 100 C, mine does around 105 C.
The actual fan switch is the bit which screwes into the engine that has the 2 male pins.
If you pull something that doesn't have 2 pins, you may have the wrong thing.. you probably wouldn't want to short the wrong plug.. wait till someone confirms this *is* the fan switch... I'm 99 percent sure, but it was a few months since I did mine so it may have 'moved' in my memory