iMac Intel 21.5" (EMC 2389)
Used this iFix it guide:
Just buy these specific suction cups and spudger if you're going to do this. Seriously, it's like, $20 and you got piece of mind. I wish I could have gotten the 2.5"-3.5" Drive Adapter from you guys too, then I wouldn't have had to get a crappy one that didn't fit right from Amazon! Oh well, the Crucial m4 128GB I used is really light, so I just plugged it in and let it rest on the metal. Works fine.
Use towels when handling the screen, and try to remove as much dust and hair from your environment as possible or else you will have blurry screen fa sho! Microfiber cloth needed.
Don't forget to check out this guys post, really helped:
Especially don't forget to load HDD Fan Control or your iMac will sound like it is always taking off! There's no port for the temp cable to plug into an SSD, so you're forced to use this software to read the SMART temp instead of from that cable to nowhere.