Not sure what you mean by serial number?
Read this;
http://challenger.mpoli.fi/phpbb/viewto ... =4119#4119
In the example shown you can see that the stampings on the cowl and radiator support are the same as the last 8 digits of the VIN. Except that the model year and plant code digits are the other way around than they are in the VIN.
Also many of the parts on the car have date codes of some sort to show what year they were made. Usually a date a month or so before the car was built. I have seen a manufactued date stamp on some body parts too. The rear valance behind the licence plate for example.