Are you installing the system on this hard drives? If not and they're just attachments for additional storage, then you should have no problem.
If there's an OS installed on them that you want the data from and you didn't separate your /home folder, you'll have to copy that data to another drive, remove/replace the OS installation, and then copy the data back.
Yep. I think that we're on the precipice of what's to come.