Hell freezes over: You can now upgrade your Mac at home | ZDNET
How to Upgrade the Memory in the iMac Pro (late 2017) - YouTube
Install memory in an iMac - Apple Support
How to Upgrade RAM on MacBook Pro, iMac & More | AVG
Amazon.com: OWC 32GB (2 x 16GB) PC19200 DDR4 2400MHz SO-DIMMs Memory Compatible with Mac Mini (Late 2018), 27" and 21.5" iMac (Mid 2017), and Compatible PCs (OWC2400DDR4S32P) : Everything Else
Install memory in an iMac - Apple Support
hardware - Can I add different size RAMs to iMac 5K? - Ask Different