Davenporter -
Here is the info for parking downtown and the shuttles to/from Ryan Field. I'm going to park in the Church Street ramp. I've been to several Iowa/NU games and other NU games. I have never seen the Church Street Ramp fill up on game day. Especially a morning game. The Maple Avenue ramp is very big I can't imagine it will fill up either. You can catch the shuttle within a couple of blocks walk from either ramp.
Looks like the shuttle from the Church Street ramp picks up by the public library this year. The Maple Street ramp will pick up at Clark and Maple, right by Chili's.
The buses start downtown so that is the best place to catch one. They tend to fill up the closer you get to Ryan field.
After the game you may have to wait in line for several buses before you get on one. It can be difficult to tell the line from everybody milling around and exiting after the game. Be sure to ask people where the line ends.
I'm staying at the Hampton Inn in Skokie. I usually take Dempster to downtown then turn left onto University or Hinman to get to the Church Street Ramp. That helps avoid some of the downtown traffic. Or you can take Emerson directly to downtown Evanston from Skokie and park in the Maple Street ramp.
http://downtownevanston.org/sites/downtown-evanston/downtown-evanston-map.pdf
http://www.nusports.com/sports/2015/3/18/GEN_201401018.aspx
Let me know if you have any other questions.
Hawksky