I recently completed this project for my Youtube channel. The model kit was purchased as a downloadable .stl file from http://www.mezgike.com. I printed it at 200% to allow me to add LEDs to both the weapon and the power box on the back of the fist. The switch is located on the base with the spent shell casings and it's powered by a coin cell battery. I found, accidentally, that the coin cell will last about 10-12 hours when left on before it's almost completely drained.