Is it possible to mount two (or more) SATA HDD's in an external enclosure and NOT have them in a RAID configuration.
I want to have two drive letters (example E & F)for the two drives.
That's a very interesting question!
How external drives are configured in a case depends on the case controller, where the choices usually are a single drive, RAID 0,1, or JBOD.
To have 2 or more separate drives kept separate, you would have to have a system with separate controllers and separate SATA cables.
But you could configure them as JBOD (Just a bunch of Drives) as one large volume (not striped), and have 2 (or 3) partitions (E:\, F:\). Where the partitions fall on the drives would depend on how big you made each one, but one drive wouldn't be E:\ and the other wouldn't be F:\.