Nice work on the brakes! In my 20's I flew a Piper Colt for years. It had notoriously bad, ineffective brakes. They were just enough to get you stopped from a slow roll. I really learned to plan ahead and to do careful energy management! It also had no flaps. I learned how to do slips to get into short fields with trees on the approach end. Good experience!

Could wear a chest/helmet mounted cam for the instrument panel/pilot pov

I have seen in different lexane instalations that holes were drilled litle larger to allow for temperature expansions and also support materieal flexing. It will prevent bolt holes in lexan to crack. Just idea. Have no personal experience with installing lexan on a wing of airplane.

Lexan for the fuel tank cover, why? Why not 1/8" ply fabric covered and painted to match.

Regarding the fuel cap, could you use a different thickness gasket to change the angular position of the gauge face when the cap is tightened fully? I'd like to know where the gauges came from! I just ordered my tanks, but I'm a ways off from using them.

The brakes were considered optional when I built the ultralight version of this plane. I chose to install them. And one day, I pulled up to the "hold short" line, preparing to back taxi the runway at our small, local airport. I had my head buried in the cockpit, fiddling with the radio and GPS when I heard a pilot yelling "stop, stop, stop" in my headset. I had relaxed my hold on the brakes and was slowing rolling forward. When I heard "stop, stop, stop", I slammed on the brakes and stopped right on the line, just as a Cherokee touched down on the active runway. I hate to think what would have happened had I not had brakes. The moral to the story: if you're building a plane, the brakes are not optional. Unfortunately, the walk of shame to apologize to the pilot I nearly killed was also not optional.