The first step in doing any boat project is finding the proper tools.
That means completely emptying the lazarette because they are always on the bottom.
One hour later I find the tool.
Using a splicing needle to splice a shackle into a halyard.
The core in this line (Marlowbraid) is slippery and difficult to work with. I use a slevagee hitch (the red line) to get a grip on it.
It requires a great deal of pressure to pull the needle and core through the braided cover. One end of the line is connected to a winch and the other to a cleat. Start cranking!
Work the last bit of core manually and
there it is.
Finished and it only took a few hours.