Jeff,
I just tested this in my lab, so results may vary slightly depending upon your environment configuration
In my particular tests with my database and logfiles on the appropriate LUN's, there was no action of dismounting that occurred after running the Configuration Wizard to point it to the same locations as it was originally stored.
You'll also find some references to your questions in the SME Admin guide on pages 145 and 146
You will probably want to make sure you have appropriate downtime/outage arranged if you need to move things other than your Log/DB data
(Examples being, MTA queue path, SMTP queue path, etc) (see page 147 of admin guide)
The best part is you can run the Wizard to get a feel for what changes likely will need to be made, and whether an appropriate outage can be arranged if needed.
Hopefully this addresses what you were looking for Jeff.