Basically the drive is in the Mt Pleasant-ish area... last year we drove for about 2 hours I think... went up towards Cadillac and in a loop that ended up back in Mt Pleasant. We didn't really go "Up North" much more than that. There is a lot to see in that area though, and a lot of great twisty roads.
As far as bringing "wife/girlfriend/one-night-stands" along - feel free. Last year my fiancee and another members girlfriend went along... they had a great time talking to each other at the photo stops while we all talked cars
From the looks of things I may actually be driving my XR on the color tour too!! Thats pretty exciting... assuming I can find a release lever for the T5 I have in my XR... Ford dealerships seem to not have the part that I need listed anywhere... *mutter*