So a normally simple upgrade from standard 2005 sp3 to 2008 was a little but of a pita.  Backed up all the dbs, including system dbs.  Then go through the upgrade steps.   It failed with an error about not being able to find sqlncli_x64.msi.  Try a repair on sql native client, and fire up upgrade again.  Same error.

Uninstall sql native client, try upgrade again.  Failed for an error about a service stop or start not responding.  I couldn’t manually start sql agent.  So I extracted the sp3 files using the -x flag and reinstalled sql native client.  Agent started, but the upgrade failed again.  Check the “add/remove” programs again carefully and find sql 2008 native client also installed from about a year ago.  I uninstalled that and ran the upgrade again, and success!