Tacho does not work since son crashed the car, have checked the fuse, the connection at coil and have removed and refitted the instrument cluster, but no luck sor far. How do I detach the odometer reset button from the instrument cluster so that I can remove the Tacho. As I am not a mechanic, is there any way to check the operation of the Tacho once I've removed it apart from looking at looking at it? TIA Nev