I was able to successfully fish a messenger line through the top beam before I replaced the wood with a chunk of aluminum. I don't think I could go there today.. I used a piece of old coated lifeline to go from the port side eyeball light hole over to the stbd side eyeball light hole.. I left a good messenger there after running the speaker wire.. without the messenger, it would be tough getting around the mast support block. if your mast support base/compression post have been repaired, it might be much easier to go a different route, through one of the bottom beams either forward or aft of the settee. I have run messengers from the panel, aft to the lazarette through the wire run, and forward to the eyeball socket ..