Q: Can I move xServe (Late 2006/3 GHz) Internal RAID drive to another identical xServe?

I have two identical Late-2006 3 GHz xServe units with internal RAID controller.  Both are setup for RAID 5 and both have x3 750GB drives.  One is a production unit and the other is a spare.  The production unit was showing that the RAID was viable but degraded.  Drive 2 in the production unit was showing as 'roaming.'  In RAID Utility, I clicked on the 'roaming' disk and told the RAID Utility to Make Spare.  During the rebuild process Drive 2 came up as 'failed.'

Can I move one of the spare unit's 750GB drives to the production unit?  If yes, is it as simple as plug-and-play or do I have to somehow erase/reformat the spare drive?  Please keep in mind that I am not a 'tech head.'

Thank you!

xServer Intel Dual 3 GHz/4GB RAM

OS X Server 10.4.11

RAID Utility 1.0 (29)