I had the opportunity to match one back in the day. I had a mount and I found out the Cmp had the M1C to match it. So I called them and they put a hold on that serial if it ever came up to call me. They said they had to wait till it was graded before it could be sold.

Long story short i waited several years and I lost interest and sold the mount. Then about 2 years after I sold it I got the call.

I have always kicked myself I wasn't more patient. I think Dave McClain said there are only a little over a 12 matching sets he knows of. They are very rare.