Serial/VIN# location(s)?

So… I decided to do a body swap on my 65 CJ5. I found another Jeep (57 CJ5) with a great body, but no drivetrain. I know that there is the serial number tag under the hood on the firewall driver side, but it got me thinking, is the serial number stamped on the frame anywhere just out of curiosity? I looked in the shop manual where it shows serial number locations on different components, and it didn’t show anything for the frame, If not, what would keep somebody from just taking the serial number tag off one body and putting it on another body Without swapping to the other frame? As far as I can, tell, there is no difference in the structural design of the two frames of the different years. I need to either swap the drivetrain from my 65 and put it in the 57, or swap the body from the 57 and put on the 65. I want to register it as a 65 because the 65 was a Naval Air Station Jeep and that’s what I want to restore it as, and the other was not.