Expand drive space raid 1 array smart B110i sata RAID controller

[mosconim]

I have two raid 1 array  2 SATA drive (250Gb) raid 1 each one hosting the C:  and E: drives.

I need to replace with 2 new SATA drives (1Tb) the Array B (E: drive) 250Gb old drives

From what i'm reading i'm not sure if I need to take the server offline to have the drives rebuild or not. 

I tought to do this:

1.Create a good backup.

2.Check the drives for errors using the SMH (System management Home Page)

3.Check the drive(s) SCSI ID's, the must match the bay numbers.

4.Ensure you use supportet drives.

5.Remove the first drive off-line: Shut down server (Power off)

6.Remove one of the drives

7.Repower server and choose F2, interim recovery mode, during SA scan.

8.Insert new disk.

9.When the first disk has complete rebuild, replace the other disk on-line.

10.When rebuild has complete - Extend the logical drives, using the ACU (Array Configuration Utility) this is an online operation.

First question/doubt: Point 8: Insert new disk. When I insert new disk ? After press F2 ?

The advantage of removing the first drive off-line, is that if the first rebuild fail, you can put the first removed drive back in its original position (off-line), and you're back where you started.

I understand I will need to expand the partition if I use the built in smart array tool.

 Any info/procedure would be greatly appreciated.

(Proliant ML350 G6)