Here is a very small sample of tracks from Alton to Hamburg. I also have a route that is in gdb form, and when I try to convert it to gpx it gets all wacky.
So if someone wants that as well just let me know. Keep in mind the portion from Alton to Grafton is on a dedicated bike trail, but the highway parallels it to the ferry where the bike trail breaks off and heads to Pere Marquette state park. Hope this helps.