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
How to Add An SSD To The 27" iMac (Late 2015) - iFixit Repair Guide
🛠️ 🖥️ 🍏 💽 iMac 27" 2012-2015 Hard Drive Replacement or SSD Upgrade - YouTube
How-To: Now's the right time to swap your old iMac's hard drive for a fast new SSD - 9to5Mac