Here's a pic...
The Z-bracket is on the middle. After I installed it, I decided I wanted to add more brackets (because the wood roof is very thin and I wanted to be sure not to have any panels blow off while driving). You can see the L-brackets now on each side, each with one bolt through the side of the solar panel. In my case, I screwed AND VHB taped them to the roof. In your case, you will just use VHB tape to the roof.
If you'd like to see some other tips/tricks on a solar install, you can check out my experience here:
https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/30217540.cfm
Good luck.
Chris