In this video below you can see how HDD Caddy is installed in the Asus K50IJ.
1. Turn of your laptop and make sure you everything set and ready.
2. Put your laptop upside down.
3. Remove the battery.
4. Remove the screw at the bottom of your laptop.
5. Remove the screws at the sides of the laptop.
6. Then remove the bottom plate of the laptop, now the internal hardware ie exposed.
You can also upgrade your ram memory.
7. Remove the screw holding the optical drive.
8. Push the optical drive out the laptop.
9. Transfer the bezel and metal bracket from the optical drive to your HDD Caddy.
10. Put the HDD Caddy in the optical bay.
11. Put everything back together and you are done!