How to rmove the IP

IP? there should not be nuts holding the tach in, there should be clips on the ears for the screws to thread into, If there are nuts, you can try removing other instruments for access. Have you cleaned and lubed the cable ? checked the cable routing? you don't want any sharp bends in the cable.

I need to replace my Tach. It quit reading Tach hours. How do you remove the IP enough to get to the Tach? It was replaced only 339 hours ago.  It would require a very talented mouse to hold a wrench on the 4 nuts while loosening the screws. Thanks! Tom