I think my temp gauge is faulty, i've had the instrument panel in pieces and there is no needle for it to rest on the gauge appear to be all electronic and the temp gauge motor seems to have a mind of it's own.
That’s just the one clock, are the stop pins missing?
If the clock is damaged, you could replace it with another from a scrapyard.
3 screws, Green arrows to remove and unplug, pulls straight up.
What year is your car? You may not have an outside temperature gauge fitted, see picture.
Edit, Don’t apply any force when working on the PCB board, either to the mileage clock or the time clock as the can be easily damaged.
There is a sensor in the front of the engine under a removable plastic shield with the Mercedes star logo on it, this sensor is where the temperature gauge gets its reading, worth having a look at that, yours is a later car than mine so am not quite sure if that is correct in your case.
The fuel gauge could be a separate issue at the petrol tank sender. Or both are related to a faulty connection at the PCB or its connection plugs but don’t know too much about all that.