Quick question for you @trurl, is it possible to assign the parity drives as part of the array, start the array and see if all the space is used up?
Then stop the array, and assign those 2 drives as parity?
To be specific, I added 4x20tb drives. 2 of them were assigned as parity drives, but I can't remember which two I assigned of the four.
Looks like it should come up as unmountable per this thread: