For a small site of 15 users I recently setup GW2012 using just ext3
(going from Netware budget was an issue)

The the Groupwise system is on a Volume called 'GW' (created using NCPCON)

Rather than reconfigure GW is there any I can say create a NSS volume called

is this what I need to do or is there an easier way ?

Shutdown GW copy all data
delete existing GW volume
Create NSS volume called GW and Restore data