Such a fun ride! I wish we were going. I have done it 4 - 5 times - first did it in 2001 - got platinum my first year which was a shocker! (women really do have an unfair advantage in that) and bettered that result a couple of times after. It is a fast fun century course. You should be well prepared with your training program - and being a local, knowing the course.
This was also DD's first century on the tandem. I think she was 10. That year I lost them - not sure if they were ahead or behind me. They were ahead and I puttered around long enough waiting for them or trying to find them that I probably finished an hour after they did.
It really is a great time of year to ride in Tucson. I have yet to do Mt. Lemmon and that's on the bucket list.