There is a huge difference in tempertures between an RV roof and a sailplane tailboom. I have had a solar panel glued on my tail boom for 2 years and it is showing no signs of melting or discoloration of the glass beneath it. Oh, and I NEVER have to remove my battery and charge it!

I would not do this. The temperature that will be generated under the panel is going to be very high, potentially weakening the structure. Those who glued flexible panels on top of their RVs know what I am talking about. I have seen melted flexible panels.