These lighting kits are almost essential to make the droids look "complete". I've done a number of builds now with these lighting kits, but the instructions for this one were among the worst in terms of visible wires.

If you followed their instructions, most all the wires get routed to the back of Chopper and the junction bricks are mounted to the legs - super visable and very lazy. I was able to get all the wires routed and hidden (for the most part) inside the body. Inside the left and right sides where the legs attach, there's two 1x4 bricks used to limit the leg movement range. I was able to replace those with the junction bricks - there was just enough room to run the 5cm jumper cable and then route the USB connector out the bottom. Since the junction brick is slightly higher, it probably does limit the leg movement slightly but it's not noticable and the result is so much nicer.