It appears that it is only possible to encrypt the boot drive with FileVault. Does that mean that I would have to boot from the defective SSD (it is a clone, after all) and then encrypt it? I'm thinking that it would be easier to drill several holes in the drive or, better yet, expose it to a nuclear blast. 
Jon
macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
| 
