Ray Charles & 6 More Legends Of Rock 'n' Roll Live (1988)

Legends Of Rock 'n' Roll Live was recorded in Rome and originally broadcast on Cinemax in 1989. A gathering of r&b, blues & rock greats, belting out 15 songs followed by an all-star jam, all seven of them in peak form.

Paul Litteral - trumpet; Crispin Cioe, Arno Hecht - tenor saxophones; Chuck Leavell - keyboards; Dave Edmunds (musical director), Robert Funk - guitar); Phil Chen - bass; Terry Williams - drums.

HBO Archives has numerous clips of backstage scenes and interviews made during rehearsals for this concert. The concert took place in the Palalottomatic Arena. Some tapes are dated 21 November 1988, but the concert poster that's visible in some of the interview sets clearly has 17 November (one of the edited tapes is dated February 1989; I guess that was not too long before the broadcasting date).
Looking at that poster, and listening to Ray's surprised response, it becomes clear that B.B. King was a last moment replacement of Chuck Berry.
Some of the rushes of the interviews and of the rehearsals can be watched on the HBO Archives site:

• Interview with Ray, part 1: Ray sitting indoors: smiling & rocking: talks about the artists he's playing with on show- they're innovators; explains that he is not a specialist (like the others), but a utility man; expresses excitement about seeing back James Brown, Bo Diddley, BB King, Fats Domino, telling jokes and lies to each other. 
• Interview with Ray, part 2: Ray explains that music is made one way; talks about accolades and being called a legend and a genius; his musical influences; the various music genres & musicians he likes. "Music is written the same way for everybody. I wished the world was like that."
• Interview with Ray, part 3: Ray talks about Little Richard & Jerry Lee Lewis being one of a kind; explains the key to his longevity; his musical diversity; mentions future projects.
• Concert rehearsal rush with Ray: being lead on to stage, finding piano and microphone.
• Concert rehearsal rush with Ray: band on stage playing and stage crew working.
• Ray Charles leaving stage after performance, meeting & hugging Little Richard backstage (no sound).
• Ray sitting backstage in chair, having fun with Bo. 
• Interview with Jerry.
• Interview with Maceo Parker, declaring his desire to work with Ray.
• More rushes (without previews) described here. 

First U.S. air date probably was March 5, 1989.

Reuters has archived an item on a press conference (without Ray), that aired on 16 November. The documentation of the reel is still including Chuck Berry in the line-up.
The content smells a bit like a desperate PR attempt. The statements of Diddley and Brown are hilariously far away from "reasons for doing the concert".
In the documentation Reuters explains that the concert was "[...] staged for the benefit of Unicef", and that it "[...] has already cost over two million dollars to stage, but more than 50,000 dollars has been set aside for Unicef. Live coverage of the show is to be broadcast in France, Germany, Spain and Italy. Television stations in Europe and around the world are signing contracts for a later edited version. On Wednesday, some of the stars practiced their songs on stage and talked about their reasons for doing the concert."
But during the press conference Bo Diddley said on tape, "Rock 'n Roll is dead? I'm not going anywhere no way, Rock 'n Roll will never die." James Brown said, "Nobody has the monopoly on the feeling, nobody has the monopoly on God - may I go please?" Source here.

DVD: Image Entertainment, 5 December 2000, ASIN: B000051S5Q.

Mess Around:
[You'll get the whole concert here!]

A Fool For You:

Whole Lotta Shakin’ Goin’ On / You Don't Love Me No More (Jam):