I found a 24" iMac from 2008 in the garbage at my job, after taking it home I ventured into learning how I might repair it. After a lot of troubleshooting and tests, I decided I needed to pry it open and swap the hard drive. I bought this tool kit to assist with replacing the hard drive and everything went smooth! There was a lot more work after swapping the drives, but the tool kit made it possible for me to bring it back to life.
Taking it apart wasn't really the hard part, especially since I had learned the root of the problem was the fact that there was NO HARD DRIVE inside the %#*@ thing! After putting in a drive and getting a copy of OSX(the MUCH more difficult part believe it or not) it runs fine now. The main issue I was concerned with was the fact that I didn't have the heavy duty suction cups, but honestly the one provided in this tool kit was (barely) adequate enough to pull the glass panel off the iMac, which magnetically snaps into the body itself. I guess that's why they suggest the heavy duty suction cups. Aside from that, the torx security bits worked great, I didn't manage to strip a screw or damage the heads.
Find an iMac in the dumpster? CHECK THE DRIVE BAY. Think it's a hardware issue? CHECK THE DRIVE BAY. Missing folder icon at boot? CHECK THE DRIVE BAY!!
In all seriousness, had I just bought the tool kit immediately and popped it open, it would've saved me about a week of tinkering, but lesson learned!
A side note unrelated to the tool kit, using a USB installer did NOT work for me on this model as it refused to recognize any disk not connected to a SATA port, so my solution ultimately was to make an installer on a separate partition on the same hard drive. This worked out well and would also have saved me about 4 days of tinkering, so now you know!