The AR type is the only one with a visible split ring
The third photo just hides the split with shadows
I have many of these rims well over 30 and this is what they look like
No other rim has these forward facing characteristics of the half visible lock ring
There is an updated version in later 50s that had more round on the outer bead ring and you can mix and match the parts with this earlier style in the first post.
The details of the rim are stamped on the outer ring and you need to carefully strip the rim to bare metal to read it.

I have both types of rim on my farm
I’ll try to take detailed photos of each this week
If I remember
-s

Last edited by 2ManyTrucks; 07/26/2022 6:20 PM.