This doesn't help you since you have no DL status, hate2fly, but for those Medallions on Delta, I suggest calling SMS to handle doing the upgrade.

I did the same thing for a trip back in April. What I did was pretty much what FTraveler described, except that I called SMS to both have my certificate issued and do the upgrade. What SMS did was check availability and make the upgrade reservation and send me the upgrade certificate.

Then I took my original coach (H class) ticket and the upgrade certificate to the DL ticket counter at the airport and they issued me a new ticket in business.

I originally called KE, but they seemed to be confused about how to handle doing an upgrade with a DL certificate. SMS, on the other hand, knew exactly what to do and I was off the phone in about 15 minutes. I did have to call KE for a seat assignment, which was no problem once SMS handled the upgrade.