A lawn chair, a pair of galoshes, a bunch of new scouts.
Make sure that the guy playing Uncle No-Legs knows the bit out of Monty Python and the Holy Grail by heart. This would be the place where they are learning about the holy hand grenade to kill that rabbit.
The guy playing Uncle No-Legs bends his knees back until he can stuff them into his galoshes. He then is put in a lawn chair and sits there the whole time the skit is going on. Do this before it is your turn to go on and carry the guy onto the stage in the lawn chair.
Have the new scouts gather around Uncle No-Legs when he announces: Now it’s time for another story from Uncle No-Legs. Make sure that the new scouts know how to do the right emotional acts without laughing the whole way through.
Another guy(who also knows the Monty Python bit by heart and can do voices) crouches down behind the lawn chair without being seen and begins to do the bit while Uncle No-Legs is lip-syncing. When the time comes for: “Skip a bit, brother” have a guy that is offstage do it. If done correctly, this will have the audience rolling in the aisles.