You start by temporarily installing the panel and trace around all the frame tubes.
Once completed, you remove the panel, mark off your holes (usually about 2" apart), and then drill with a 1/8" drill bit.

Again, install the panel temporarily. I used some clamps, but you can use screws or drill a hole for a rivet to hold it in place. The panel is now a template for drilling the holes in the frame tubes. Again, a 1/8" drill bit is used. Remove the panel and clean up any metal shavings.

Silicon all the frame tubes where the panel will touch. The assembly manual says you can do this before drilling the holes in the frame tubes, but then the metal shavings get mixed in with the silicon. I think its worth the extra step in removing the panel after the holes are drilled to clean up the shavings.

Mount the panel and put in lots of rivets. I hear they make air rivet guns, but since I don't have a compressor, I'm forced to do the old fashioned way. My hands are really tired. I started off with a cheap rivet tool. That lasted about halfway through the drivers cockpit floor. This necessitated an emergency trip to the hardware store after first tool broke and silicon was drying on the halfway riveted panel. The new, more expensive tool is working fine. The moral to the story is don't buy cheap tools.

Here is the mostly completed trunk area. The red and black post are the remote charging posts for the battery.