This may be a long shot, but I'm trying to see if anyone had a lead on digitized copies of Rubberneck magazine, which was published in the UK by Chris Blackford from the mid-80s to around the turn of the millennium. In particular, I'm trying to track down issue 19 from 1995, which had a long piece by Nick Couldry titled "Turning The Musical Table: Improvisation In Britain 1965-1990" (see scant info here).