Upgrade PR4100 with drives removed from another PR4100

[Erick_Larson]

I have two PR4100s, one older than the other that have distinct functions in my system. PR4100-10 has 4x10TB drives. PR4100-8 has 4x8TB drives. I have 4 new 14TB drives to go into PR4100-10. I have been cycling the 14s one at a time and allowing rebuild to preserve data on PR4100-10. I want to put the 4x10TB drives into PR4100-8. When I put a new drive into PR4100-10, it is added to the array and rebuild begins. When I put the 10TB drive that was in PR4100-10 into PR4100-8, I get an alert that a drive has been added and I should go into Change RAID to add it to the array. If I do that, it says that it will remove all data. Should I be able to use the previously RAIDed drive as an upgrade in another RAID system and preserve data? Is there a trick?