PID Controller for Ball Joints

I'm rather new to Gazebo and I can't find this in the API anywhere. How do I control a ball joint using 3 PID controllers (one for each x-y-z axis)? Would it better to create 3 separate revolute joints that are orthogonal and create the controller this way? The reason that I ask is I'm creating a small robot arm that needs all 6 DOF I've gotten XYZ translation down using prismatic joints, now I need to add the rotational DOF for the end-effector. My current idea is to create a ball joint between my end-effector link and my second to last link and control the RPY of the joint using 3 separate PID controllers.