I had a forced landing a year ago. Fuel starvation. I have 2 poly insert tanks in the right wing. After flying an hour I looked up at the fuel level super low on fuel. Turned back to the airport watching the air bubbles going into my header tank. I learned I only have about 4 minutes of cruise running off the header tank. My engine never sputtered just quit. Lucky I had a harvested bean field within gliding range. Landed without any trouble. After rolling to a stop and taking a few deep breaths I heard a tricking noise. Looked up at my inboard tank and it was filling up with fuel and trickling down into my header tank. Went outside and found the vent tube on the out board tank was facing backwards with fuel all over my wing. It must have created a vacuum in the out board tank, so the inboard and header tank ran dry. I just let the outboard tank drain into the inboard tank then turned the vent back into the wind, started it up and flew back to the airport with no problems since. Make sure your vent tubes are facing forward. Wasn't rocket science to figure that one out.
I took the padding out of the middle of the seat between pilot and the passenger. This gives you a little more room and doesn't restrict the flaps. You could epoxy a small wood ball to the end of your flap handle.