VIN numbers

SO numbers don't have any coding to them

What I mean is they are sequence number for the assy line.

Maybe a dart was made and the next car down the line was a barracuda

The next 3 were darts and then 5 Barracudas

The sequence number means nothing more than which vehicle was built before the next.

I have never heard of a VON number.
VON is Vehicle Order Number.... And goes back to the number on the original order form... So it has very little bearing on knowing anything about the car it's attached to.... One car could be a V200 Valiant & the next an Imperial Crown... Followed by a Hemicuda....

The exception to "very little bearing on knowing anything" would be those VON's that have a letter prefix.... The letters mean different things, my cheat sheet is trapped in a locked hard drive so I don't have the codes but it could be as trivial as being a leased car up to a factory demo or an A12/AAR-T/A