Telemetry radio has been working fine attached to bottom of Nova. Therefore, I bought a 15cm SMA cable and moved radio inside Nova and the antenna comes out the side of body. It's a tight fit, but radio is in channel between PowerBoard and shell. Only thing cable is really touching is the slight edge of ESC white nylon socket.
EDIT 2015-01 : This is the my old Internal layout. It has since been changed and optimized.
EDIT 2015-05 : Since the above pic, I had moved the 915mhz radio back outside/underneath Nova. I have now tried moving it back inside again (during gimbal install). I didn't want it in old location because GPS is over there now.
This is the new location. Notice FrSky antenna moved to top of RX (still at 90 degrees to back one). If this all passes interference and RSSI testing, it stays here. I will just add a bit of foam tape to prevent vibrations between radio and case.
Verified 3DRobotics 915mhz Telemetry radio settings. ECC is on. While slower through-put, official docs say it is recommended and supposedly it has better distance range. Yes, you can change settings on the slave radio from MissionPlanner (without removing it from quad).