When i rode the WB Empire Builder from CHI on 5/13, they had a sign saying to check in near the Metro Lounge. I showed the lady my tickets and she gave me the little paper strips with the destination, seat numbers (with a sticker), and the door number. The sign was gone about an hour before...
While not on the national Train Day, Union Depot in Saint Paul runs its own Train Days in June. They already have some good stuff announced for this years event. Train Days 2023 - UNION DEPOT Last year they had one of the new Chargers on display as well, though they kept it running for some reason.