https://claremont-ca.showmethead.com...lery/18923233/
Here is a early set of Cragar SS 15 X 4 rims
This is how I would describe the rim in the link
Direct bolt
Round spoke
Round spoke with narrow outer rim
No bead lock
Differences to look for:
Center section differences
Round spoke with a wide outer rim
Round spoke with a narrow outer rim
Direct bolt
uni-lug
Bead locks
No bead locks
Todays wheels have :
Uni-lug
or
Direct bolt acorn nut
Flat spoke center
Flat spoke center narrow outer rim
I think there might be differences in the rim itself
I would recommend doing a thread search on the forum, there has been some very good and detailed threads on this topic.