What I did when installing the fat z-bars. I removed the whole control assy from the right side of the bars ( easy when changing the bars or risers ) 2 screws for electrical bits and 2 allen bolts for the hardware. then I slid the throttle sleeve off the end of the bars. I loosened the nuts for the throttle cables where they enter the assy ( take note of the position of each, I counted the threads ) to give slack to the cables. Then you can kind of work the 2 cables out of the sleeve. perform the reroute and then reinstall in reverse order.
Mark