You should be fine in Dearborn. If you're near Garden city in dearborn even better. I am just exagerating a bit about Detroit. Just keep to yourself and don't walk around in the "not good" areas after 8:30 and you will be fine.
Dearborn will be okay. It's not far. Maybe 15 minute drive to Cobo Hall? Just take I-75 all the way downtown.
Stay in your group, and don't get rowdy with locals.