I'm thinking to use the aluminum UNISTRUT stock on the roof edge where I can screw down in some wood side edges and use the panel Z angle to bolt to the panel and the Unistrut.
This is how UNISTRUT is used...
Google Image
The Unistrut will allow me to slide the panel ON and OFF as needed and not put a hole in the roof except on the very edge of the roof. I could probably only drill into the side of the panel up near the roof just as easy using a L bracket for the Unistrut going across the roof.... I already have a few things mounted to my roof side panels...
An installed solar panel would look something like this perhaps...
Google Image
Haven't checked into the cost of these UNISTRUT units yet.. probably high dollar stuff...
Roy Ken