Yes, 60* is the industry standard for factory style and most other conical seats on wheels. Whether they are aluminum, steel or whatever. If wheels have a conical seat, they are generally 60*. I think there are exceptions such as some OTR trucks and heavy equipment.
That's why I wanted to make sure with my previous comments, because true to form around here, there was information left completely out that was taken for granted everyone should know. You know, crystal ball info. lol
