Hi Jared.
With Steve's permission maybe we can leave this here for a day or two but it should go over into the Wheels section or else the General Discussion section gets too long. If Steve's happy for this to happen I'll move it in 24 hours.
The lack of traffic doesn't mean it's not seen. When you post there or there is a reply it will always show up in the "Show unread posts" selection which I imagine most people use.
Also, someone only with an interest in wheels and tyres might overlook it in the sheer volume of the General section.
I can't answer your question but maybe someone who has larger diameter wheels might.
Having said that, I think you might need to ask the supplier. Then ask them for offset figures and the size of the centre cap hole.
Nice wheels BTW.