I know NW on-line check-in allows one to change their FF number, so you could book on NWA.com, using your CO elite number to get the EUA, then switch it at check-in on-line and still get the upgrade, while putting your miles on NW.

I do believe the CO kiosk will also let you do this as well. Never tried the CO.com web check-in coz I don't fly them anymore :-)

[This message has been edited by thezipper (edited 03-24-2003).]