@Brett_Abela A very belated welcome to the Rockstor community.
In this context it is risky and tricky to apply additional udev rules as it is already the case that udev can’t tell them apart: udev authors chose serial for a reason. The rules would have to use some other element than serial with with to assign a serial after the fact as it were. That might be usb bus id or the like but then switching drive locations would break things, potentially badly.
To my thinking this would make the described hardware inappropriate and most likely unusable with Rockstor. We have seen enclosures like this before and it’s not a good show that they hide their hosted drives serials, or plain lie about them, and consequently upset udev’s ability, and consequently Rockstors, to tell them apart.
Can you say the make and model number of this device?
And what is the output of the following command when the drives are in the enclusure:
lsblk -P -o NAME,MODEL,SERIAL,SIZE,VENDOR,TRAN,TYPE
Linking to your other similar post on this issue from way back (sorry I missed that one):
Thanks and hope this helps.