I have an NEC NP50 and one of my clients broke the leg in such a way that I cannot unscrew it with pliers/vice grips. I've already tried removing the bottom cover to see if I could get to it from inside, but the electronics are attached to the bottom in a non-obvious way. Since its one I use for work I'm hesitant to merely keep unscrewing until I can get to it - I wanted to at least look at a service manual to see if its worth continuing my attempts or better to turn it over to a certified NEC technician.