1. Micro switches
2. Rotary encoder wheels
3. Rotary 2 phase encoder detector
4. Rotary encoder LED
5. 4 MHz Ceramic resonator
6. Connector and wire

To remove the PC board, the optical encoder wheel must first be removed.  Simply push on the plastic holder with your thumb and pull the wheel axle up. It should come right out.  Do the same for the other optical wheel.