Electricity and sound
The mainswitch which turns on and off the powerstrip is reachable from the coindoor.
I 've also installed a standard powercord on the fluorescent lamp behind the marquee.
I bought this Creative 2.1 speakerset: the Sub will be placed on the bottom of the cabinet. The satellites will be replaced by the existing internal speakers which requires some soldering.
See here the subwoofer with the plugs and wires to the cabinet speakers.
The result is amazing: it sounds very good!