RE: CG Super Chipmunk sheeting issue.
Do the servo tray thing. It just plain looks good. I built one last year. It was a fairly easy build. I put a ST 75 in for power. I fully sheeted the wings ( for strength). My maiden flight, I had a dead stick due to bad carb adjustment on the ST. It hit pretty hard with no damage to speak of. The only thing, with the extra weight, it doesn't manuver quite as quickly as it should. Trade-off, weight for strength. The plane flies like a dream, no bad habits that I've found yet. However, I definitley won't fully sheet the wings on the next "Chippy"