Removing 4 disks and a parity disk - then rearranging disks to other controller

Hello,

Current setup:

• 12 disks in array (with 2 parity disks)
• 1 ssd cache pool
• 2 unassigned disks (for couple of vm's)
• 2 LSI 9211-8i raid cards (in "dumb"-mode)

I'm about the reduce the power consumption of my array by:

1. removing a couple of old and obsolete disks
2. removing one parity disks (got two) -> this one needs to be a data disk again (or at least a spare)
3. physically moving disks to 1st raid controller so I can remove it

Not sure how to approach this. I think, due to the vast amount of changes I'm going to make, the procedure would be:

1. Move all data to the disks I want to keep.
2. Backup really important data as well as docker appdata.
3. Stop the array.
4. Physically remove obsolete disks and move the other disk to the 1st raid-controller.
   
   And I'm uncertain what the next steps are (i want to keep the cache as it is):
    
5. boot the server (array is not going to start obviously)
6. new config (which setting)
7. as parity-disk, select the one that is still there (but that parity is invalid ofc)
8. select the remaining disks as array disks.

The 2nd parity disk should, if I'm correct (and if i want to use that as data instead of spare),, be visible as unassigned disk and add it to the array..

When that is done I should be able to start the array and the parity will rebuild itself - I'm I close or are there some flaws in the suggested procedure?

Regards

Sjoerd