[Rick Parker]

I believe that all the wheels are initially cast and subsequently machined leaving the mounting pad, center hole to slip over the threaded part of the adapter. Then after the order comes in for a specific offset and bolt circle, the wheel is fit into a lathe, the height of the pad then reduced to create the required offset and the inner hole enlarged to allow for a flush fit against the face of the adapter while accepting the 45 degee portion on the adapter. I don't think the angle plays any actual part in the registering of the wheel. It's the OD of it and the pins themselves.