The door post recess is different:
http://67-72chevytrucks.com/vboard/showthread.php?p=7605048


Also for what it's worth and maybe not be appreciated, I've had trouble with 47-51 latches holding the door closed (the door can pop open).
The attached picture shows a red arrow of the ratcheting mechanism (I apologize if the parts are not oriented correctly).
If this is a bit worn, the door can move by itself.
Maybe this is the reason for the change to the 1952 design.
Attachments
Door Latch Comparison.jpg (65.33 KB, 60 downloads)

Last edited by buoymaker; 02/15/2021 12:05 AM.
"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."