Replace RAID 5 array with larger HDs, reinstall Windows 2003 on PowerEdge 2600

I currently have a client running a PE 2600 server with W2003 and a PERC 4/di RAID 5 with three drives, 37 GB each.  The C partition is 12 GB which has finally proven far too small.  I need to replace the three drives with three 73 GB drives, configure a new RAID 5 array with them, then reinstall w2003 on the new RAID.  What's the best way to do this and then be able to still "see" the current drives?

Thanks!