Get the climbing harness
I use a bosuns chair on one halyard to be hauled up and also a rope brake/rope grab on a second line - usually another halyard cleated down on both ends. A rope brake slips over the rope and can easily slide up the rope. If you fall, it will lock in place as it wont slide down the line. If at all possible, ALWAYS have a safety line. I realize that it is not always possible if one halyard is missing.I am planning on buying a climbing harness, it it much more comfortable than a bosuns chair. My Bosuns chair is very uncomfortable if you have to be up there more than 15 minutes. Tony B