I don't understand why you are using a gyroscope? If you are replacing a pot, then you would want absolute angle which a gyroscope won't give you. A gyroscope provides angular velocity. Still would produce 0 degrees/second.
If you want an absolute measure (inclinometer) you could use an accelerometer. I use the ADXL345. Adafruit has an excellent tutorial and Arduino code for SPI. You would not be limited to any number of devices with SPI. The accelerometer measures acceleration and since you are interested in absolute angle, you could simply consider your local accelerations (movement) to be insignificant compared to the 1g gravity always imposed. Simple trig gets you to the 3d angle you desire. This will take a bit of math.
The IMU6150 has an accel/gyro and the IMU9150 has accel/gyro/compass and the fusion in the device can provide the Euler angles for you thus requiring no additional trig. However, and a big however, the code for the 9150 is not for beginners and most of the available code DOES NOT WORK.
Richard