I don't spend my spare time with Park Tool stand and Allen key. But many, especially in Germany, do so. And often end up with horrible sensor voltage values (and their consequences).
Question for this thread. I just cleaned up my TMM4 sensor on my ST2S. I was surprised to see that the fourth screw in the photos above (the one NOT circled in a color) also threads into my TMM4 sensor. The sensor has threads for the rack screw. My ST2S TMM4 sensor definitely has four mounting bolts and not three as shown above.
It also seems strange that rack weight would get coupled into the torque sensor. That wouldn’t be first thought for design.