I don't think that loosening the standing rigging will do it for you, to be honest. I suspect that you will either have to get the mast removed or lifted so that you can get under it. If I was doing it, I would remove the mast and check it out along with the rigging - too good an opportunity to miss!
Leith (rhymes with teeth) is the port of the City of Edinburgh in Scotland. A Leither is someone who comes from that area.
I must go down to the sea again, to the lonely sea and the sky - I left my shoes and socks there, I wonder if they're dry?