It all depends on how good you are with electronics and soldering. You will need to cut the wires enough so that you can solder them to another saber, you will need wires for the switch, board, and LED. Not hard if you have solder before and have basic knowledge of electronics but if you don't, it may be better and safer for someone else to do it
Here's a link to TCSS showing how to build a saber with sound (We can only talk about them, no other saber company)