On the front side of the HDD Caddy there a few mounting points. Those mounting points are aligned with the front of your HDD Caddy. So obviously the bezel of your dvd drive should fit on it. However sometimes it can be difficult to fit the bezel on the HDD Caddy properly. The mounting holes do not seem to be aligned with your original dvd bezel.
So here is a trick. Push the dvd bezel frontally on the HDD Caddy does not work in most cases. The small bulges on the inside of the dvd bezel have a small clamp. If you try to mount it straight on the HDD Caddy those clamps will block the mounting holes.
To get the dvd bezel correctly mounted on the HDD Caddy you have to follow the instructions below. Consider the angle of the clamps and make sure does are going in the holes correctly and in the correct order. We start diagonally and make sure the right clamp is going in first. Put pressure with your finger and bend the dvd bezel carefully and now continue with the rest of the clamps.