I heard Cooper interviewed on the BBC, and he admitted he had been a bit put out by Ali's grandstanding and boasting - until, that is, Ali quietly mentioned to him that it guaranteed that they'd sell twice as many tickets and they'd be splitting a much bigger purse. After that he had absolutely no problems with Ali's spiel!
Cooper also said that they are still regularly in touch and that, despite Ali's motor problems and speech slurring, his mind is still remarkably sharp.