I can't find my LP of this, and so have ordered the 3cd+dvd set of this. It adds "Live in Boston" 1986 CD, and on the DVD "96kHz / 24-bit PCM stereo" (whatever that is) and Derek Jarman's film. £15 amazon.
Have you tried scanning it at 90 degree rotation?
It might give a different result, this approach has worked for me in the past, with a hologram I think, (essential for clear cassette tapes).