On my old ZL1 1LE it was the last few numbers in the vin as it was a very limited production car. Same goes for my WS6 that I sold to my son. But I am curious how Dodge does it as well, and if it would only be restricted to cars such as the Redeye, etc.
For individual configurations, you can get that by emailing PLMCRZY the last 8 digits of your VIN# to the email address in purple upper right in this image (it is an example of what you'll receive). It's $25 now