Why do you assume they would do anything to Space Mountain? It's still one of the busiest rides in the park, and is an iconic attraction.
That could easily be made to be a space assault and incorporate projection TIE Fighters and use laser lights and flashes to simulate blasters and put in crazy stuff like that. It would be a re-skinning, but would look pretty cool! Pop in some classic music from "Here They Come" before the Death Star battle.