Looks like you would have to buy the right side hinge, the gas shock and something to anchor it to on the top.
It certainly has one. It's concealed behind the right taillight assembly.The titan does not have a gas shock. If it does it is hidden and does not feel like a typically shock. From what I can tell the ball mount is tucked away in the corner of the bed side, there must be an anchor point that attaches to the ball. All of the assist is done inside the hinge with a clock spring.