Sounds like fun!! I say do your own thing and ride your own ride. If that's faster than the slower women but slower than the faster men- then so be it. Chances are you'll catch some of the men towards the end anyway.

Count me as one of the ones who is surprised that you haven't completed a century- I know you're on your bike ALL the time.
I hope your ride goes really well- please report back this afternoon when you're finished to tell us how it went.