Finally the correct HDD Caddy arrived for my mid-2009 MBP. I have bought an earlier one which does not fit and i just chuck it aside. I did not take a video of the replacement as i wanted to do a quick swap to verify the caddy works. Those circled in red are the screws and connections which you have to remove in order to umount the DVD drive. You need to unplug the SATA connector from your DVD drive to fix onto the HDD Caddy. Please take note that you have to reboot your machine in order to see the new drive as i booted up from sleep mode and using disk utility will just hang. i did not waste the drive which i had replaced earlier with the Samsung SSD. 1 TB of junk data to keep on my Mac from now on.
If you are interested in the HDD Caddy which i bought, visit Aliexpress link here!