You know what would work better (it’s at least adjacent geographically) it’s fantastical land is late 19th century/turn of the century as opposed to firmly being 1920s, and has a bangin soundtrack: Coco.
Take some of the steampunk portions of the land of the dead and remove electricity from the normal world (without addressing it at all so most people won’t notice) have it be a sequel. On the first lift have Dante and cat Pepita animatronics grasping a letter (cat) and skull guitar (Dante.) As we circle the drop, a ring of cacti and Marigold flowers replace the briar patch. At the top of the second lift have an minimal animatronic Miguel read the letter inviting him to a reunion concert tonight of Ernesto and Hector (who writes saying he forgave Ernesto) and to attend all he needs to do is strum the guitar. As we go around the outside the lullaby instrumental version of Remember Me starts to play, rounding the turn we see another minimal movement animatronic Miguel give out his yell and strum the guitar as we drop.
The Ernesto version of Remember Me starts playing as we round the bend into the show building and using screen effects like Alice in DL, marigold flowers on either end of the chute along with orange floods in the water cross the marigold bridge into the land of the dead in the area where the geese are fishing. As we turn another bend we bypass a street full of skeletons dancing and signing Remember Me with Ernestro who is being piped in by speakers from the concert. As we round the corner (where Brer Bear was hanging in the rabbit trap) we enter the stadium and we get our first two fully articulated animatronics of Miguel and Hector signing and dancing to Un Poco Loco. Of note both are wearing Marigold flower boutonnières on their chest. We pass into the backstage area as we see the family enjoying the show back stage and Emelda getting ready to go on next. Strangely every family member has a Merigold flower as well. The song ends to applause as we see Ernesto (who does not have a merigold flower) standing by the drop say come down here Miguel, I need to show you something. After the down up drop we find Ernesto explaining to Miguel that he did all of this to lure Miguel back so that he could kill the boy who ruined his death. Ernesto AA being where Brer Bear was, Miguel running away where Brer Fox is and in between a couple of bodyguard henchman. We drop, with Emelda signing La Liona above we enter an underground cave and bodyguard henchman pop up and down reach to our boat trying to catch Miguel. Of course right before the final lift Ernesto catches Miguel and tells him he’s going to throw Miguel off a cliff so no one will ever find him. However, as every log starts ascending the lift in the area where the vultures are now two Giant Cat Eyes will open, squint and then close as we hit the lift. As we get to the top using the shadow projection we see Hector or Emelda (it switches) confront Ernesto for his betrayal tell Miguel to grab his flower and then say Pepita! and whistle. Right before the drop we have a fairly static figure of Ernesto holding Miguel by the shirt but in time with the audio Ernesto head will turn around to reveal a scared look. Instead of “Briar Patch” we here Miguel I give you my blessing right before the drop. Not noticed from any angle other then this spot observant guests will notice Ernesto’s scattered bones amongst the cacti as we drop. At the old Zip-a-dee Landing, it’s now black lit and we are in the Rivera courtyard and we have the entire clan (living and dead) recreating Proud Corizon. Besides Hector and Miguel being again advanced electronics other eye draws will be the Skeletons all glowing orange like the movie, and Emelda silently stroking a full size alebreije Pepita (also glowing) and Dante fluttering above and of course fireworks exploding in the sky. Where Brer Rabbits house now sits will have the Rivera ofrenda instead.
Now some caveats, yes the steampunk stuff in the land of the dead and electricity are anachronistic, i have no idea what to do about retheming the top of the mountain and I would prefer Splash staying. However if forced to retheme to a recent IP that’s what I would choose as Mexico is at least close enough to the American Frontier. Give Tiana a show in the old Mermaid theatre instead.