temperature and fuel guage
 

I have a 2001 a3 1.6, the temperature and fuel guage are reading the wrong levels on the dash, however temperature is normal and the fuel light still comes on. I have been told that I need a whole new intrument cluster, the mechanic told me this would mean my millage would be reset to 0, Is there a way around this? Can the clocks be repaired? Or can the 2 guages in question be taken out of the new instrument cluster and inserted into the old one ? I am keen to leave the millage as it is as the car only has 20k on it, and messing with it now could lead to questions being asked when I go to sell.