Roughly a month and a half in advance, I emailed [email protected] and let them know that I'd be in the Chicago area (with my family) for a week's vacation and was wondering if they could fit us in for a tour. After about a week or so, Jody emailed me back to let us know which day worked best for them. So I agree with @nowakster... it took some time to get a response but they eventually did. All-in-all, it was a great experience and appreciated them taking the time out of their busy schedule to accommodate us.

Good luck, hope you get a chance to see the factory.