Don't know the answer to your question but I would certainly go if you had the chance. I visited one night real late with Dave Shuten as tour guide. If you'd like to view the adventure thread search icons of speed and style auction and my name. Should show up. Perhaps a quick call to the place would give you hours of operation to the public.
I will be at GNRS wed - sun, but I'd be happy to arrange a tour for you... email me @ DMSHUTEN@AOL.COM