I would open a support case via mysupport.symantec.com asking for assistance on how to move the data.
When setting up the MSA20 as a DAS< make sure to use all the WIndows best practices to the RAID config, NTFS formatting, disk alignment, and perhaps turn on collections. There were also a few critical SP's from HP to fix some firmware issues under high disk I/O that would make the MSA20 disappear from your SA controller :eek:
And upgrade to EV8!