I checked it all out today...
The switch it coming on at the right rad temp... but whilst the rad is only reaching 90 degrees for the fan to cut in... the temp gauge is reading 110 as that reading is taken from the Stat housing. that right? then the fan kicks in on speed one and the temp gauge goes back down to around 90...
I have gone and bought a 3 way switch to mount on the dash so i can turn the fan on manually if i want. Also... can you get stats that open at lower temps? and would it be worth changing the black temp sensor on the stat housing.... incase its giving weird readings?
hope that all makes sense!