Just installed a new internal 4TB HDD + OWC Temp Sensor in a Late 2012 27" iMac; with High Sierra. Drive seems to be purring away quite happily - so hopefully physical install OK. However new drive is not showing in Disc Utilities. So I need some #101 Terminal command line advice. 'diskutil list' - produces the attached list. Do I use disk1 or disk2? And what are the required Terminal commands to put things to right? Thanks in advance for any help.