As a 6' 4" guy who's taken the Amtrak from Syracuse to Chicago and back - the Lake Shore Limited, even! - here's some advice:
The train is an overnight trip - it rolls out of Syracuse at about 9 - 10 PM, and gets into downtown Chicago at 10 AM. Except the train may be late. And that the train may get into Chicago closer to Noon. And that if you're over 6 feet tall, you will be uncomfortable in your seat.
So, you'll need to leave Thursday evening. Enjoy your Friday afternoon in Chicago. The train coming back is an overnight trip, too. Enjoy your Monday afternoon in Syracuse.
The best place for damn-sleep-we're-playing-cards is probably the lounge car. They tend to pack you in like sardines in coach, so getting seats near each other will be tough. Never hurts to ask, though.
The best, best way to get to Chicago (I think) is to conspire with a friend to get a Viewliner Roomette. It costs $240 (or so) one way, which isn't cheap, but it comes with a USA today, bottled water, a sink/toilet in the room, and meals in the dining car, and you can split it with a friend, since there's two beds. (It would be about $400 round-trip from Upstate NY.) While you're not sleeping, you can fold a table down and watch America roll by. It's the Romance of the Rails, though, that will be priceless.
