We get it from the 11 digit VIN he posted. I thought he was just giving the partial vin as I have seen many times. The B comes up as a /6 and the car comes up as a 1972 Dodge Dart. I am a Barracuda person so I went off what he posted and corrected. No big deal if it is wrong because I am sure he will fix it when he gets a chance.
Based off what was posted above you should have the full 13 digit VIN stamped on it.