If you were going thru Southeast Nebraska, there's a big OLD yard outside of Wymore, NE that you could literally get lost in. But that's a bit out of the way. The National Cowboy & Western Heritage Museum in OKC is interesting if you're into that. The National Route 66 Museum in Elk City, ,OK is worth an hour of your time, IMO. If you're looking for Railroad theme, Union Station in KC is pretty awesome, a little off your route though.
