As I read it, the author says the procedure works just fine to create an external that will boot an M1, barring the issue with ejecting the data volume.

And, theoretically, anyhow, CCC should be able to clone your data volume to the newly created installation.

Sounds like a solution, albeit an expensive one.

The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire