Mast light works as I ran wire directly from battery to light and lit up. I then tested for power coming from wires out of the deck area and no power. Then went to electrical panel to check fuse and it's ok. To check switch at mast light , I put mast light wire on marine radio switch since I knew radio worked and still no power from wires out of deck to mast light. so it's must be the wiring, trouble is the wiring is buried in headliner with no easy access. Anybody deal with similar issues? Could rig something up from switch outside of headliner but would look rinky-dinky.