Got the RSSI working on PPM channel 6. The RSSI value is still bouncing from 92 to 99. I just need to do a test flight and see how drastic the RSSI value goes down once the plane is up in the air. I had to upgrade the firmware on both Crossfire tx and rx to v1.06 to get the RSSI on PPM working.
10km test flight. 500mw stock TX and RX antennas