DING DING DING SOUND THE ALARM!...

If I remember correctly from last year’s sale, we were getting reports of the CNC version come two different ways. Some had untouched cast chambers. Others were CNC profiled chambers, which likely accounts for the difference in size.
Mine were ordered assembled and they do have CNC chambers, but I forget what they measured.

That's right, I forgot about that. Good call. There's so many posts from last year, I wish I could go back and find that set of posts, because as I recall I wasn't able to find a part number for an assembled head with cnc chambers, but you had a set.