Don't know whether you are aware of the Peterloo song I was given by Salford Historian, Eddie Frow when I was involved in the earlier project
I gave it to Sam Richards and Tish Stubbs for their "English Folk Singer" - I think they used the tune I put to it.

"Fiends"
Actually, the S.W.P. people I was dealing with were a fairly friendly and articulate crowd - just ignorant, as far as folk-song was concerned, and somewhat short-sighted as far as working-class culture was concerned -isn't that always the way
I got to meet Vanessa Redgrave (sighhhhh) while I was in contact with them; her husband was running the project
Jim