The tach has to be removed from the rear of the instrument pod so you will need to remove the pod to get to it. Are you asking for information on removing the pod?
I won't say that there is absolutely no way to remove the tach without removing the pod, but I tried it once and gave up in frustration. There is no easy way to remove the pod either. I have also tried just removing the mounting bolts and tipping the pod enough to get to the tach, but overall I would say that it is easier to just disconnect everything and pull the whole thing out where you can get to it. Dropping the steering column helps also.