Though The Muppets appeared on the show twice, this collection includes only their
last appearance from July 19, 1984 on disc 11. The episode also features Dabney Coleman who worked with The Muppets on The Muppets Take Manhattan.
Here's a clip from the appearance.
Here's hoping a future release will include Jim Henson and the Muppet's October 6,1977 appearance.
You can order the set which also features interviews with Andy Warhol, Salvador Dali, and Norman Rockwell through Amazon.