I am a windows user who has previously upgraded my SSD but now am working on an unfamiliar iMac that belongs to my wife so want to get my ducks in a row…. Parts List: https://www.amazon.com/Samsung-Inch-Internal-MZ-76E1T0B-AM/dp/B078DPCY3T https://www.amazon.com/Inateck-FE2004-External-Drive-Enclosure/dp/B00JQTO8TU https://www.ifixit.com/Store/Mac/iMac-Intel-21-5-Inch-2012-2017-Adhesive-Strips/IF173-005-1 I already have the IFIXIT Tool Repair Kit. My plan is as follows: Clone HD to SSD using Samsung Data Migration and the above the external enclosure. Then use the following instructions for opening Imac. https://www.ifixit.com/Guide/iMac+Intel+21.5-Inch+EMC+2638+Hard+Drive+Replacement/28781 Concern: Read TRIM can be an issue but unclear if I have to change any setttings and how to do it. Concern: Read Fan running continuously is an issue because heat sensor or ??? Question: Do I need a bracket or spacer to hold the SSD in place? Is there anything else that I am missing?