To get the real answer, check with the DMV office in your state.
Yeah, ...I'm not so sure that will be a correct answer.
To the original poster, your question is very ambiguous -and therefore you will be getting many answers that vary in validity. The Ford Factories (-the proper term for those were called Branches by Ford) technically did not issue a VIN to the vehicles they produced. This was solely done at the Rouge facility prior to any assembly of vehicles when they stamped the Engine.
To expound on this, each Engine that passed final inspection at the Rouge was stamped with a sequential number. Information on this is found in the daily Foreman's Logs. After final tests (-Q/C) and the sequential stamping had been performed, the completed Engine assemblies were then warehoused for shipping to one of the many Ford Branches at a later time. Something to note, -at the time of shipping the Engines generally (-i.e. most often) were not shipped sequentially even though that might have been the intent, ...nor were these numbered engines installed sequentially on the assembly line once they had been warehoused at the individual Branches. Understand this further by looking at the picture below.
When the Agencies (-a/k/a Dealers) received the vehicle, it was acquired without any Certificate of Title and was only transferred with a document that today we know as a MSO (Manufacturers Statement of Origin). To be clear, many States at that time did not issue Titles to the purchaser, -and some States even issued a Title to the Purchaser listing the 'year model' at the time the vehicle was actually sold by the Agency, ...which could hypothetically mean that a 1929 model year vehicle that was sold (-for the first time) months afterward in 1930 or 1931 could have been titled as a 1930 or 31 respectively.
Now to muddy up the advice given above, we DO know that while Ford's protocol to the Branch's was to stamp the frame with the same number as was on the installed Engine, we also know this did not always happen for various reasons. This has been documented. Therefore, the ONLY absolute was the first Engine that was installed into the Chassis while on the assembly line had an Identification Number. If someone is making a legal argument about the proper VIN, it really is the Engine's number.
Protocols and mandates have changed since the Model-A was produced, and a great legal argument can be made that for the 1928-1931 Ford Model-A, the Engine number
IS the VIN, -and lifting the body to check for a Frame number is solely for the purpose to verify if any tampering has been done in the past.
I testified on the behalf of one client that in modern day vehicles, we find the VIN has been affixed to hoods, fenders, doors, and many other components on the vehicle. By installing a used hood from a vehicle onto another vehicle with a different VIN does not change the VIN for the vehicle it was installed on. I went on to explain that if a Model-A received frame damage sometime in its past, replacing the frame assembly with a used but serviceable frame from a different vehicle was an accepted and legal practice. At that point, the Judge ruled that if the different number on the frame was not presently being used, then the engine's VIN would serve as the proper VIN for the vehicle.
My point in this lengthy post is, often times hearsay and 'he said/she said' info is stated enough times where people choose to regard it as factual. The Model-A hobby is seemingly one of the worst at posting this 'stuff' on social media. Just because your local DMV office says one thing does not mean it is factual. Often times laying out the facts in front of a Judge changes everything, ..and at which time the DMV abides by the Judge's orders.