I also might be reading it wrong but trying to find the production number for my car has been elusive to me so just looking for some help and extra eyes look at all the info to make sure I’m understanding it all as I am new to the Mopar family.
Welcome to the money pit!
MyMopar.com get your cars or Plymouth Factory Service manual, also wiring diagrams, they are in the FSM but others might be easier to read
ClassicCarWiring.com great laminated full color wiring diagrams best 25.00 I have spent.
Chrysler Historical new contact info. Stellantis Historical, because you have a 66 you can get a copy of your IBM card, it takes a few months and many are really hard to read BUT I can help with that. It has codes that are not on your fender tag but not a complete build sheet either.
As for production numbers as in total number of wagons made for a particular year there are sources on the net that have numbers but some might be suspect.
Your fender tag has a SO number on it, that is the sequence number, IT IS NOT associated with the VIN except on the IBM card and on a build sheet. The SO and some other bits MAY (I don't know when they started doing this) be stamped on the body in the left trunk lip under the weather-strip. On a wagon it MIGHT be under the seal on the left in the rear hatch door opening. And it MIGHT be on the radiator core support under the radiator coolant sticker typically on the drivers side in front and to the passenger side of the battery.
The stamped body numbers MIGHT read like 6220112345
6 = 66
2 = assembly plant, Hamtramck, MI
201 is month and day 101 thru 930 are Jan 1 thru Sept 30, A01 thru C31 are October 1 thru December 31. cars with build dates before August are build in the year their model number is, Cars built from August thru Dec were built the year before their model year. So a 66 built on 915 would be a 66 model year built on Sep 15 1965 and a 66 model year built 115 would be a 66 model built on Jan 15 1966
12345 is the SO number off the Fender Tag
As for VIN, it will only be on the VIN tag WELDED to the door pillar. There will be 2 holes that look like pop rivets should have gone in them but they are just alignment holes for when they welded it on the pillar.
The FSM will have the codes and descriptions of what the VIN should look like
Have fun and don't get upset if a grouchy old man gives you a hard time here on FABO, there are lots of us and sometimes we forget our manners
