When I was younger it was no problem to do 1100 mi. We still do more distance the first day of a trip. I would only try this if you both can agree and stick to stopping if you get tired. Drive to the farthest point and plan on resting for a whole day. Then do your sightseeing on the return trip. Last couple of days for getting home.
I'd suggest stopping at each states welcome center, once your a 1000 mi out, and gather brochures for anything that looks interesting. You can study them on your rest day and pick some stops for the return trip.