This is pretty old school but you just can't deny the talent.

Boy that is really familiar. I am wondering if there was a CD of this concert ... or maybe a TV documentary?

This one was done in 1996 I believe. It was done on DVD and VHS and was a follow up to an album they did back in the 70's. I remember you used to see the album in the cut out bins all the time. All three are accomplished solo acts but every now and then they would get together and do some concerts together and they were just magic.