I think that's the correct approach.
Remember that everyone there is a professional and you are all there to work. Get on with the project because everyone's reputation is at stake. And then, after a few days, as you say, just say something like, "Look I know how this probably happens all the time, and it is a real bore to you, but I am a big fan of the film, I have the book you did the Forward to, would you mind signing it for me...?"WATCH HIS REACTION CLOSELY!!!
If he doesn't say much - he probably won't want to. Of course if you become friendly with the man - and especially if you get pissed together! - I imagine you will get a bit out of him. If that's the case, come on here and tell us
I've just looked at the book. I think your choice is either title page or Forward. I'd say title page, because he was a main character and you will be able to add the others later.
Good luck, and let us know how you get on.
The key thing to remember: you are there to do a job.