Once you have taken the instrument pod out, you should see half a dozen 8 or 10mm hex screws holding the thing together. Just start taking it apart and it should all become fairly self evident as to what is wrong, the odometer is a single unit in itself. As well as the cables that are plugged into the back, you will need to unclip the speedo cable to the back of the pod to remove it, this requires nimble fingers! - just be careful not to damage the circuitry on the flexible circuit board on the back of the pod.
