Bob, for many years I shipped very large pieces of freight using a freight fowarder and consolidator out of Chelsea, Massachusetts called Seajet Express. Their website was not working today, so I don't know if all is OK there; try calling at (617) 884-0991. I worked with a fabulously responsive and efficient woman named Gabrielle Hiemann.
They always handled everything for me through their domestic and international network.
If that does not work, start looking up "crating and packaging" and "freight forwarders" or "freight consolidators" in your area.
Everything I shipped needed custom crating, and the custom craters usually had knowledge of the freight forwarders and consolidators.
You'll usually find them located near the airport, in your case, O'Hare.