Yes, they changed their position  on the cars over the years and were not always easy to find. In the fullness of time (in the 1980s) the company was required to conform to government regulations on these numbers..forcing them to adopt a minimum number of alpha numeric numbers in an easily accessible place, most often on the bulkhead or the bulkhead toolbox or the hidden part of the hinge of the bonnet (the nickname of the bonnet maker on one side and the VIN on the other). However, the earlier secret places remained in use for many years even into the more modern era. Within the Morgan communiity, the only important numbers are the few Morgan ones at the end of the long modern VIN.

With older cars, the numbers were scratched or stamped, most often, on the crossmember behind the seats. Of course, time and paint can obscure these but trust me, they are there.

PERSONAL MARKS FROM THE WORKS 
by Lorne Goldman

This placing of personal marks and nicknames on the cars was a charming custom from the old days. Morgan workers would place their nickname or sign on hidden

places on the car..expressing the pride they had in what they had made. The most extreme example was the Work's rebuild of this author's car, where the entire staff of the Morgan Motor Company signed the floors underneath the seats.

The vehicle identification number (VIN) is a 17-character code assigned to every new vehicle produced. The VIN contains information about the car's manufacturer, location of construction, year and model information. The VIN is used to track the history of the vehicle so people can learn about a vehicle before purchasing it. In addition, it can be used to confirm stolen vehicles. In order to decipher the VIN, you need to know which digits represent which aspects of the car. 

1. Locate the first character of the VIN. This number is used to denote where the car was built. The number "1" or "4" means the car was built in the United States, "2" means the car was built in Canada, "3" means the car was built in Mexico, "J" means the car was built in Japan, "K" means the car was built in Korea, "S" means the car was built in England, "W" means the car was built in Germany and "Z" means the car was built in Italy.

2. Determine the car's manufacturer by looking at the second character of the VIN. For example, an "H" means the car was made by Honda or a "1" means the car was made by Chevrolet. However, there are some manufacturers that use the same character. For example, both Audi and Jaguar use "A" and both BMW and Dodge use "B." The third number will denote the division of the company that built the car.
 
3. Use the fourth through the eighth characters in the VIN number to find out information about the car's features. Information denoted by these numbers includes the engine and body type of the car. These numbers are determined by the car manufacturer and are not universally standardized.

4. Skip the ninth digit. This digit does not tell you anything about the car. Instead, it is a check digit based on the other digits in the VIN.

5. Determine the model year for your car based on the 10th digit. The pattern includes 30 digits starting with A through Z (with I, O, Q, U and Z not used) then the numbers 1 through 9. The pattern started in 1980 with "A". You can also use the model year chart (see resources) to find the year of manufacture. The 11th digit gives information about which plant produced the car and varies among manufacturers.

6. Find the serial number based on the last six numbers. Depending on the manufacturer, this number may be reset to "000001" each year or each model or may just continue to increase.