HID lights installation

[springroll]

I am new to this forum and here I am posting my first message. I have a 2003 KJ and looking to installing a set of HID lights. I have made a few attempts, but I couldn't even move the caps that are holding the headlights. Can anyone provide some details for me to start with, pictures will be even better.

Thanks in advance

 

[Trodo]

Do you mean the circular, ribbed knobs retaining the bulbs themselves. They have a cam lock, turn a quarter turn and pull away from the housing.