@palmercr even has an OpenSCAD design all ready to print, which I did. Haven’t tried the fit. The one I designed and printed works so well and is so tight that it’s just going to stay on there.
This is the topic you’ll want to read about an extender flange for the exhaust port.
Caliper measurements are here:
Wait a minute. I’m reading that topic over and you posted in it. Am I missing something here or did you forget about it.