RAID migration to expand

Ok, I have a dell PERC H200, Server is SBS 2011

I had 2 x 500GB drives in raid 1, I upgraded them both to 2TB each and thought I would be able to expand the raid......apparently I cant.....so I have a plan... can you let me know if you see any issues (and i have enough drives to perform this all and end up with 1 raid and 1 separate drive (we use the separate drive as a full internal backup to compliment the off-site backups)

Start:
SLOT A: 2TB (HARDWARE RAID Ai)
SLOT B: 2TB (HARDWARE RAID Aii)
SLOT C:
SLOT D:

Step 1:
SLOT A: 2TB (HARDWARE RAID Ai)
SLOT B: 500GB (HARDWARE RAID Aii) - Rebuild Raid
SLOT C:
SLOT D:

Step 2:
SLOT A: 2TB (HARDWARE RAID Ai)
SLOT B: 500GB (HARDWARE RAID Aii)
SLOT C: 2TB (HARDWARE RAID Bi) - Create RAID
SLOT D: 2TB (HARDWARE RAID Bii) - Create RAID

Step 3:

HARDWARE RAID A: (Windows RAID Ci) - Create Mirror over two hardware RAIDS
HARDWARE RAID B: (Windows RAID Cii) - Create Mirror over two hardware RAIDS

Step 4:
SLOT A:
SLOT B:
SLOT C: 2TB (HARDWARE RAID B)(Windows RAID Cii) - Break Windows RAID
SLOT D: 2TB (HARDWARE RAID B)(Windows RAID Cii)

Step 5:
SLOT A:
SLOT B: 2TB (NO RAID)
SLOT C: 2TB (HARDWARE RAID B) - Tell windows raid not to bother any more
SLOT D: 2TB (HARDWARE RAID B)