I have some mp3's of the cassette release, forget where I downloaded them from, maybe UbuWeb. Two tracks:
The Peristaltic Airwaves [41.58]
Plato's Cave, Rothko's Chapel, Lincoln's Profile (w/Sonic Youth) [38:04]
Never really made it through the whole thing, couldn't get past Mike's over the top vocal contribution. If it turns out they are not going to be commercially available, I can post it here. SY contribute intermittent dissonant atmospherics.
I also have mp3 of the excerpt on Tellus #18, maybe also from Ubu Web?:
Excerpt From "Plato's Cave, Rothko's Chapel, Lincoln's Profile" [13:22]
Here is a link to UbuWeb's page for Tellus #1, with tracks by SY, Live Skull, Rat At Rat R, Rhys Chatham, etc...
http://www.ubu.com/sound/tellus_1.html