Indulge me, please. I cannot control myself, this is like finding the holy grail, only better. The Mothers of Invention perform the piece, Progress, at the Royal Festival Hall in London in 1968 with the BBC Symphony Orchestra augmenting the band. I have this on a cd entitled the The Old Masters. But this is the piece complete with Theodore Bikel and Roy Estrada's extraordinary performance as the rejected Mexican Pope. There is a little extra commentary from band members explaining some of the sequences. This piece was expanded and eventually became the genesis of the 200 Motels Film a few years later. I am as happy as a little girl! BTW, The opening sequence with Don Preston, who is one of the pioneers of modern electronic music and the electronic keyboard player with the Mothers at the time is very cool. Don is still around and finding new ways to derange and dementedly exploit every advance in technology as fast as the developers can think them up!