I'm about to install a pair of 180w panels to my van. My plan is to vinyl wrap my roof in chrome (chrome to help offset the heat gain of having a solar panel on the roof) then silicone the panels to that. That way if I ever want to remove them, I won't have messed up paint to deal with, just peel off the wrap
Here's a good article detailing various installation methods:
How many ways to install the flexible solar panels on the camper’s or caravan’s roof?
The main issue I have is cooling. Those panels get really hot. I'm looking for something like coroplast that would give me a bit of air gap but not just melt in the sun. The roof ribs are already fairly deep, so that's better than 100% contact, but on previous install I found that 10mm isn't really enough.
Any ideas?