Control for smilers can't be bought, but this smiley is free. It's time for the last rewind, so steal 15 minutes from your faulty plan. 5:30-5:45 PM Saturday. We meet, we interact, we sign log, we disperse. Simple.
Coords will lead you to a covered seating area near the restrooms. Plan on a group photo. Parking shouldn't be an issue, but if you're not in the area for the show, you'll probably want to park at the nearby Rocky Mountain Arsenal National Wildlife Refuge Visitor Center (park is open until sunset) and walk/bike in from the Arsenal Connector trail 3 soccer fields to the east.
Update (8/29/14 8:10 AM MDT) - I visited the Wildlife Refuge yesterday morning to test the alternate access for cachers not attending the shows. It's not going to be easy and may not ultimately be possible. I walked down to the soccer fields (from some slightly closer parking along the Refuge access road) with no problem, but there's no obvious way to cross them to the parking lot. South side is all fenced off and there was a person actually guarding the trail further to the south. Best bet appears to be just to the north of the soccer fields to where they are collecting money for parking, but I can't guarantee that it's ultimately passable. I'm upping the terrain of the cache on account of this wrinkle and apologize to anyone who can't get to the event because of it.