I think my earlier attempt to add to this thread must ahve dropped down a slot. I'll try again and hope to push the right button this time.
Following 'andymacs' original posting, the Plymouth shanty crew, who may or may not have been the people he heard at Both Sides of the Tweed, is called 'Hanging Johnny'. They have recorded the container ship song on their CD 'Yankee Clippers & Limey Traders', where they call it 'Tilbury Town'. If you want to learn shantys and other sea songs, this is a good place to start.
A pedantic complaint. Please don't call this song and others like it a shanty. A shanty is a work song sung while carrying out a particular job, such as pushing on the capstan or hauling on a halliard, (whatever that may be). Songs traditionaly sung for entertainment in the fo'csle or pub are called forbitters. What modern songs should be called, who knows? Not shantys.