Thanks for asking, RequestedDeletion.
Yes, I did finally get the upgrade done. The problem with the backup centered on authenticating ssh between SME 6.0 and MacOS X. While I haven't yet attained perfection, I did manage to backup the SME server successfully.
The second problem was truly fear of destroying the previous installation. The key element I had forgotten was the "upgrade" option in the SME installer set. With the backup completed, I decided to just "go for it", burned the 6.0.1 iso image and ran it against the server. The upgrade succeeded. Yeah!
I then used the "Latest version of update scripts" from
http://no.longer.valid/phpwiki/index.php/Latest%20version%20of%20update%20scriptsThese scripts ran perfectly, except for being unable to access contribs.org for one rpm. I used the ibiblio site for that and the installer performed as expected.
The server appears to be stable and functioning correctly.
Many thanks to Greg Swallow and the others who contributed to that effort. And to those who built the 6.0.1 iso. I appreciate these efforts very much.
So all is well in my neck of the woods.