Just found this web page:
2006_2007 Current Stock List 2007B.xls
It seems that "DBC" = PPG Deltron paint system ....... WE HAVE A WINNER!
The car in the first post of this thread was painted in "Deltron 4069 Twilight Blue Metalic Poly" = Ford "MK" or PPG "FRD.M6290A"