Just talked to Aran at the dealership. The smart car display will be at Shelter 4. That's in the group of shelters, volleyball courts, and playgrounds that are between the lake and Mt. Trashmore. There is a map available on the Mt. Trashmore website, upper right.
Parks & Recreation | Mount Trashmore Park
Shelter 4 isn't shown, but it's above shelter 3 on the other side of the path. I'm going to try and get into that parking lot next to the office sometime between 10 and 11. (Maybe if I tell the park people I'm part of the display?

) According to the earth day website, people are encouraged not to drive into the park, but park at satelite lots and take a free shuttle. But Astuto wants to be in the middle of the action!!!