When I had to re-fit that sensor, I used a deep socket on a long 3/8 extension. A locking extension is useful.
A locking wobble is nice. 
I still haven't grasped my way around the electronic fuel / ignition
&c. I do know that ABOUT two years ago someone in the 700 section experienced a temperature sensor failure that "failed differently" than usual. That confused their resident source of knowledge. Hey ho .... Jam jar diagnostics is not an entirely exact science?
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