Apple Xserve (Early 2008) DIY Procedure for Enclosure - Manual (Page 69)

Xserve (Late 2006/Early 2008) Drive Interconnect Backplane Replacement Instructions 3
Removing the Installed Drive Interconnect Backplane
Note: Before removing the power distribution board, you must remove the following:
All Apple drive modules •
Airflow duct •
Fan array •
Apple Drive Modules
Press the handle on the front of the drive module so that the handle pops out. Then grasp 1.
the drive handle, and pull the drive module out of the Xserve.
Repeat for all other installed drive modules. 2.