I am interested in this one. I think it would make stick flying actually easier since twisting  your wrist for yaw control, at least for me, has me also doing some extra roll when I don't want to. I think to implement this in the best way you may want to do some testing in SC itself.

Check the yaw characteristics in game. Do you yaw at one rate only, or does it change depending on how much twist is applied to your yoke (flight stick)? If it is one rate, then a simple switch is all you need. If it is variable, then you will need to rig something with a resistor, similar to the trigger buttons on a 360 controller.

And then there is how much range of motion do you want to give these pedals. My time on helos and general aviation showed that rudder pedals can be pushed pretty damn hard, but that may not be what you want for a gaming experience.

I'm super excited to see what you do for this project. I think  it would be absolute tits. I plan on remaking my desk into a flight sim styled station so I will be incorporating in what you come up with.