While trying to install as SSD, I pulled the part of the fan connector that's soldered onto the logic board completely...

Thanks for the info, Reece. Can you point to any type of instructional video for this? I've done soldering on guitars before but never anything with a circuit board, or this small...

- I ran into the same fan-running-at-full-speed issue after reassembly. Apparently the iMac uses the stock HD's temperature sensor, so when you switch it out it has no sensor and spins on max all the time. As mentioned above, don't pay for HDD Fan Control - use the free Macs Fan Control (http://www.crystalidea.com/macs-fan-cont...). If you have an SSD, you can leave the HD fan permanently set to the minimum (as they emit so little heat).

I read that on some 2009 & 2010 iMacs, the fan issue occurs when one of the cables is put back mis-orieneted. Apparently, one of the connectors can work right-side-up or upside-down, and if you get it wrong it causes the fan issue. 'Anybody know if this is true for this model iMac? Anybody tried this as a fix?

Not a hard install to do - I just ran into the same issues already mentioned here:

- The magnets on the side of the casing really do make working with screws a pain. I ended up using a pair of tweezers to aid me but the suggested above idea of using a straw as a guide is genius!

- You really do need 2 people to safely disconnect the 4 cables before you remove the screen. The cables and sockets are very easy to damage, so it's much safer to have someone with 2 hands or one hand and a flashlight rather than you working with one hand while holding up the screen with the other.

- If you are installing an SSD, you will need an adapter bracket. I only realized this once I got inside my iMac. With a bracket, it's no problem at all.