In our IC RE, the last panel I could remove was over the driver's seat and stairs. That panel is not as wide as the others, stopping short over the door actuator. It's also shorter, from front to back, as the rib spacing is different there. Start with that one.
You might separate the panels with hatch holes. Layout the e-door and e-windows, ours have labels above. Hopefully, you can just treat it like a puzzle, lay out and mark the knowns and deduce the remains. The less similarities in each panel, the better.
The leading and trailing edges are distinguishable. The front edge should be exposed to pax, the rear edge should appear to have been covered up by the panel behind it. The last panel (rearmost) has both front and rear edges exposed.
Realigning each screw will be even more fun than removing. I'm jealous. We had 88 screws in each panel. Now I have 1066 screws in a coffee can. Yes, I counted them all. I really put the 'O' in ocd.
Also, the IC factory applied a bead of seam sealer to the perimeter of each panel. I had to pry them loose with a flathead after removing all of the screws. Gravity wouldn't kick in until the adheasive seal was broken loose. You may have a unique bead stain, matching each panel to a mirror image stain, on the ceiling.