How To Upgrade/Replace Mid-2011 iMac 21.5" Hard Drive To an SSD! - YouTube
OWC - In-line Digital Thermal Sensor Cable for upgrading the Hard Drive in 27-inch & 21.5-inch iMac (2011) models : Amazon.co.uk: Computers & Accessories
Hard disk replacement for a mid-2011 iMac - Life, the Universe and Fishing
21.5" iMac Hard Drive SSD Upgrade or old drive replacement 2012-2017 (Including Retina) in 4k - YouTube
2011 imac 27" 32GB - final stage of 1TB + 2TB SSD upgrade (replaced HDD & optic drive). Also cleaned out the fans and case. Running 'SSD Fan Control' & 'Macs Fan
Upgraded' Apple iMacs lock out hard drive replacement • The Register
iMac Hard Drive Upgrade to SSD - Your local Apple Repair Specialists