I think this is the back of the ride vehicle. The stationary portion. Remember how when the doors open from the last pre-show room, and you see the back of the Time Machine? There was a description of this, when the doors open, a Krusty the Clown figure would greet you.
I think this actually looks pretty good compared to the building facade with the fake roller coaster setup.
"You're not thinking fourth dimensionally!" -Back to the Future
"With this place, I wanted to give them something real, something that wasn't an illusion, something they could see and touch. An aim devoid of merit."