Nothing on Bill Mason so far - but I did find this:
http://www.chez.com/pfasso/faqwaters.htm#'What does the morse code on _Radio KAOS_ say?'
[-] 13. 'What is the 'Lost Verse' to 'The Tide is Turning'?'
There was supposed to be another verse to this song, but it was removed because Waters was worried about lawsuits. He did, however, sing part of it (the last two lines) during some live concerts. The lyrics are:
Now the past is over but you are not alone Together we'll fight Sylvester Stallone We will not be dragged down in his South China Sea of macho bullshit and mediocrity
This is also who Waters refers to later in the song when he sings 'The tide is turning, Sylvester.'