My "best" modification...

A modification that I made already some years ago, and have been very happy with, was making it possible to open the upper part of the pilot door as a window (like on a Piper Cub or Citroen 2CV…). 

I have now simplified my earlier modification and applied it to both doors. While you can open the doors in flight, opening just a window reduce the risk of stuff falling/flying out and creates less drag. Great for hot summer days, both before takeoff and for flying cool with your elbow out the window...

The window frame is made of 12 mm aluminium tube ("seamlessly" joined by inserting a 10 mm tube...). The aluminium tube bend easily with a cheap 12 mm copper tube bender.  

The window will stay open by itself as long as you fly “clean” but it will close just when you are about to take that perfect photo while flying the plane with your knees. So I installed gas springs to keep them open. The perfect re-use of the door springs when they can no longer hold the entire door.

To keep the windows closed I use Citroen 2CV window latches – this is not the only similarity between this plane and those amazing french cars…