kochj -
Roger those fuel concerns

However, I've never had any of the issues you talk about. I've been flying a Piper Cub and a Piper Pawnee 15e (modified with an O.S. .25) with the same type of valve and set up for almost two years (over 40+ flights easy on each) and never had one issue. But I agree, keeping fuel off vital parts of the airframe is key. That's why I always do a thorough flight check each time I hit the flying field.
No frame damage? Check. Bolts and screws tight? Check. CG set? Check. Radio test? Check. etc.
But I'm a little anal that way.....it's part of the fun for me.