Here are 2 pictures of the mount I did on my EZglider to do the video I shared with you the past days. It relies on accessories provided in the "helmet" version of the Go Pro.
A solid wood plate is glued at the top of the fuselage, at CG location. I have inserted a bolt in the wood plate in order to rotate the Go Pro fixing plate on top. there are 2 positions: 0 and 90° which allow me to do 0, 90, 180, 270° view. So side or rear view are possible.
Then, I use the long fixing arm provided in the helmet kit in order to have the GoPro higher and see at the minimum the nose and the spin.
I uploaded few pictures on picasa: here
I flight apart the addition weigth (200g), I don't see much difference, and the EZG is even able to climb when conditions are good.
The power of the dualsky motor is great to carry everything in silence which is a plus when you fly in a quiet place.