When I press the eject button the DVD drive makes a sound like if it was trying to slide the tray out, but it struggles in va...
Here's a more hacky solution. I have a 2008 Mac Pro and a Crucial RealSSD 2.5" drive. I didn't have access to a 2.5" to 3.5" adapter, nor anywhere to buy one easily. I simply installed the SSD drive 'bare' in hard drive slot 1 by pushing it into the SATA connector at the back and then supporting the drive with a small object underneath it. The small object sits on top of the grey box underneath hard drive slot 1 (fan assembly?). In my case a small box of staples was just the right height to keep the SSD drive perfectly straight. This is probably a risky way to install it since if the drive comes in at an angle it might ruin the SATA connector from stress in the plastic. But it works for me for now.
The locking bar moves towards the ribbon cable. For me it didn't take all too much violence. Now how to get the ribbon back into place, that's a different question...
When reassembling, getting the display connector and the speaker connector reconnected is quite challenging. Anyone got any tips?
The very first model does not have the four tabs. To open this version, use a plastic opener tool and push it into the middle of the tiny space between the rectangular dock connector and the antenna cover. Move the tool to the side and push it in a little deeper. A small gap should open up at the bottom of the antenna cover, where it meets the metal. Continue using the plastic opener tool in there, pushing it in and forcing it around the edge so that the antenna cover further separates. Then repeat this on the other side. To me it seems like a very brittle piece of plastic, so be careful. But now that it's loose at the bottom you can lift it with your fingers and work it off.