Realistically, this update is going to happen in under a year (perhaps well under a year), so that timetable probably rules out drastic alterations to every scene, knowing the pace at which modern Disney works.
And
@JungleSkip, I hope your theory about the "story" being contained to a section of the ride proves to be correct. Too much emphasis on that could derail the breezy, screwball nature of the attraction.