Lots of fiddling to do yet but here is what I am headed for.
The collar will be on top of the router and the excess cut off.
Better too long than too short.
If you move the angled part up and down on the router ears the top parts will get wider or narrower.
The whole project may be a flop it wont be the first time.
Being able to deal with a failure is important.
Worth
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