I would some advice please on disconnecting a redundant telephone extension. We have the master box in our living and one spare extension in the dining room which we dont use and would like to remove. On opening the bottom part of the main box, there are six wires connected which go up the living room wall (in one cable) and go to our extension box in the dining room. Can this be easily disconnected or does it need a professional. Do want to electrocute myself!! Have added pics of the two boxes main one first and extension second. Thanks