Looking for information on sightseeing stops, points of interest between St Louis and Yellowstone, and then from Yellowstone to Mount Rushmore and returning to St. Louis. This will be about a 2 week driving trip for four senior adults. We will drive for 6-8 hours at a time and stop along the way daily, with a couple of days at Yellowstone and Mt Rushmore, as needed. Any tips and neat stop overs will be welcome. Thanks in advance.