I know not everyone is as overly fascinated by the history of the SPGB as I am, but surely this letter from the December 1933 issue of the Socialist Standard piques people’s interest.
A disputed story that’s so intriguing that it should have featured in The Monument by Barltrop. I’m guessing the Ridley Road debate would have been an outdoor debate:
https://socialiststandardmyspace.blogspot.com/2015/12/socialism-and-red-shirts-1933.html