I am having to add a wire to the harness for a deck light. I have replaced the mast wiring and plug with new LED lights and 4- wire harness. I went to install the new deck plug and found my old one had very little play. I went inside expecting to find the bottom side of the plug and cannot see it. I need to add a wire or buy the whole harness with four wires but I cannot tell how it is run. There is a wood column that runs from ceiling to floor in the cockpit but I can't see how to get into it or take it apart. Need a little help from anyone who has performed this upgrade.