GTN 650 GPS Antenna location?

[C-GTDP]

Finishing up the installation of a GTN650 into an RV9A with a dual screen Skyview system. The SV GPS antenna is located under the rear canopy screen and has worked well since installed three years ago. But where to place the Garmin antenna??? Where have others mounted the antenna?? On the turtle deck? If so, mounted a shim to get it moved up the 8 degrees to get it horizontal to the horizon??? How about placing on the glare shield??? Any other possibilities???