Pedal insert LED lights for Gotway unicycle

This is a case to accomodate one battery, 3 leds and a mercury switch.

Its size allows it to be inserted within a Gotway MCM2 and MCM3 ( but not MSuper or MCM4 ) unicycle pedal and provide a way to be seen by other people while riding your wheel (See video and picture).

Depending on the leds used, you will obtain various effects.
Here is a video showing two options:
https://www.youtube.com/watch?v=GVOQImmvStY&feature=youtu.be
They automatically switch on when you unfold the pedal:
https://www.youtube.com/watch?v=zSM35KjcctA

Here are parts that you will need.

Mercury switch: http://www.ebay.com/itm/141807317185
Batteries and charger: http://www.ebay.com/itm/181725362921
Prototype PCB: http://www.ebay.com/itm/400985368376
Battery spring plate sets : http://www.ebay.com/itm/231239955456
Leds: http://www.ebay.com/itm/400985246280

You just solder 3 leds on a piece of PCB, parallel wiring (not serial), wire to the battery spring plates with the mercury switch in between, stuff the whole thing inside the case, and give the mercury switch the right angle to turn the power on when the pedal is down (tricky, use tweezers) and you are done.
Here is a video showing the mercury switch in action:
https://youtu.be/gQ4Imk2E2i0

Just add a bit of soft foam on one side of the case so that it stays in place once inside the pedal.

I was asked to post this by someone at the world's biggest Electrical Unicycle gathering in Paris last week end (https://www.youtube.com/watch?v=Hdt5KFjgPQI)

I recommand using multi colored leds, that can sustain the 3.7 to 4.2Volts of the battery with no damage.
Some Leds will die with only 2V so check them before. Diodes can be added to lower the voltage independantly from the current.

-