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I had not seen that. Thank you, that is just what I was looking for!
Just to close the loop in case anyone else finds this.
I found it worked using the standard location, ~/.ssh/authorized_keys.
I used puttygen (Windows) to create the key and pasted it in there.
There is a dropbearkey program that will let you create keys on the Omega2+ in case you want to ssh FROM the Omega2+ to, say GitHub/Gitlab...
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