What's a Steam Box?
Since I don't own consoles, how do you use that wireless receiver with the 360 controllers?
Third, why do you want to put a mom switch on the receiver?
A Steam Box is a computer connected to a tv that can play the Steam client in big picture mode. The wireless receiver is a Microsoft product, it allows you to use Xbox 360 peripherals with your PC. The momentary switch is already on the receiver (think when you have to press the button on the Xbox to sync new controllers).
If I understand this correctly, you want to leave the receiver in the case, but you want an external button to start up the sync.
It'd be easier to just take out the switch already there, or leave it there, but either way, wire a replacement to where the contacts are for the switch. This way you can move the switch around wherever you want in the case rather than having to attach the receiver somewhere.
Correct, that's what I meant in the first post. The circular button in the photo is the tactile button used to sync. The four pins are labeled "J,S,N,:" It would be easy/quick/dirty to just solder the wire at the top of the circuit board to the leads, if I knew the correct ones. I couldn't find what manufacturer/model this button is, so I'm not sure which leads to solder to. With the device so small I'd rather not guess and check, soldering everywhere.
After that it's just a matter of lighting the switch. I haven't taken a multimeter to it, I'm only assuming the smd led takes 3v. Bumping that up to around 12v for the switch would be cool.