Sorry been away, haven't been online in a couple of days.
To recap and answer the questions - the car was an all drum setup. The wheels fit the rear drum hubs without issue. The wheels almost fit the original front drum hubs - it appeared to me that some very minor clearancing would have been needed to bolt them up.
The real issue was the car was switched to a 73-76 A-body front disc brake kit. Parts are most certainly cheap Chinese parts. One thing I did not mention before, I went down to Advance Auto and measured another rotor, it had the same hub diameter. So there seems to be some consistency in the rotor hub diameter.
As an update, I found some center caps on Summit that were available in both the original hole size, and in a larger size to fit over the hub. I ordered the center caps and had the wheels milled out to 2.95". Wheels fit just fine now. I'll post pics shortly. It'll be a month or so before I buy tires though, I've already blown enough $$$ this month.
The Minilight people have been really helpful by the way, they have offered to refund me half of the machine work costs. And their engineers lets me know how big they though the center cap hole could be before becoming a problem. All in all I'm very happy now that I've got something I can bolt up to the car. I hope noone took this thread as a bash on Minilight - the wheels are beautiful.