Hi
reisserar
You have to get to the top of the mast to lower a new line down or to pull a new line up.
You have three choices
1. Drop the mast.
2. Go up the mast.
3. Use a bridge or cherry picker to access the top of the mast.
1. Drop the mast. This will mean making an A frame and using the mainsheet to lower the mast.
Not too difficult if your mast base /tabernacle is rigged for the job.
2. Go up the mast. On a 20 footer. No thank you.
3. Use a bridge or cherry picker to access the top of the mast.
Scope out what bridges are around.
Check the cost of a cherry picker rental in your area.
You can use an elecrician's snake to feed a messenger down and then pull the halyard through.