Starting way, way back Southern and CB&Q teamed up on a run-through train that resulted in Q power running to Louisville, KY and SOU power running to Beardstown, IL. Don't know if this train still runs, but it made it at least into the NS/BN era. For a while in the early 1980s SOU used GP30/35s on the train, while BN offered GP40s and - very frequently - SDP45s.
