Thanks, guys. 24mm is as wide as I can go and I just picked up a roll of Delta 3200. The tours aren't real long and there are usually quite a few people so there likely won't be time enough inside to use much more than that. I'll probably bring 2 bodies, one for inside and one for out.
And a scary thought comes to mind. Maybe the Cambo 4x5 can make it's first debut in public.