I'm in the same boat... err, plane, as you. I've got a set of pedals i built myself that has a load cell for the brakes and separate gas and clutch pedals. Which, if i recall correctly, is similar to how the CST pedals are. Unfortunately for us, the game only allows a single axis to be used for the rudder, so there is no way to use them for rudder control since we don't have a way to combine pedals as Gisen suggested.
As a small consolation, you can map them to control the left/right braking. I still use the stick twist for rudder on my X52 Pro.