Chosen Solution

While swapping hard drives on my macbook, one of the black rubber guides on the side came out with the drive. As a result, when I reinstall a drive, the drive doesn’t sit right and the machine doesn’t recognize the drive. Is there some way to get these brackets back in place? The machine is a macbook white 13 core duo 1.87

If you remove the top case, you can easily access most of the machine. Follow this guide, at step 13 you will have access to the drive bay: MacBook Core 2 Duo Hard Drive Connector Replacement