I look at boat listings to get ideas for things I might want to do on my 1983 Catalina 36. I've gotten some really good ideas. On some interior images of Mk I C36s are these wire rigging - turnbuckle setups coming down from the cabin top on an angle going to the mast, maybe 18" long. What is that for? Does it provide more support for the mast? Is it something I should consider adding when I'm bored and have no other boat projects? It looks like the lower end goes into the mast slot (which of course would be hard to do with the mast in place).