Loosen the mounting post on the rear of the head unit containing the old XP5 phone cradle, rectangular amplifier box and speaker. Remove the 4 screws from the ball mount that is attached to the rear of the phone cradle. Set those screws to the side, as you will not be using them anymore. Remove the 3.5 mm audio cable from the phone, and from the back of the amplifier box. You will not be using this anymore. Set the XP5 cradle to the side. You will not be using this anymore.
Remove the screws that connect the rectangular amplifier box to the bracket. Set these screws to the side, as they will be reused.