I might have it. I posted links to some of the selections from Disneyland's 25th Anniversary Parade a couple months ago, and I've been waiting for my schedule to open up to continue that process. I've got the time now to convert the remainder of my cassettes to MP3s and I'll check to see if I have the DIYL show in storage.
BTY... I do have a copy of a parodied version of the show that was performed in my backyard (by a group we put together called the "Kids of the Backyard") for a Disneyland Character Department party in the summer of 1980. We even parodied the fireworks show with my sister's Barbie doll (Tink) flying over the backyard suspended on a wire. Jack Wagner did all the announcements and Don Dorsey edited the original music and added humorous sound effects. I'll post the recording in the near future as well.