Alright. Here goes.
1st: I'm not volunteering for anything like this again until I know exactly how much of a PITA it is to accomplish.
2nd: This is a much more complex little piece of felt, metal and core material than I had realized before. There is really only one flat working surface (the surfaces that actually matter in holding down the top) - the vertical section. The rest are at least slightly bowed/curved. They look flat but aren't.
3rd: Nigel or Pierce seems to have fettled with mine.
4th: Measurements are with the felt in place but calipers pressing into it tightly.
5th: If I missed some measurement that you need let me know.
6th: Santa better be really good to me for doing this
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EDIT: 7th: The piece that wraps around the roll hoop is not flat but hook shaped with a small lip at the rear most end.
YMMV