You know, I've thought about retracts. Might as well fill the whole fuse up. It can be done, tho. Gear would be much shorter, but the sixty would work fine with a small diameter three blade. Too much power now, anyway. Air tank? Bury it in the wing, or paint and hang it (them) as drop tanks, hmm. I also wanted to get rid of the stock silencer. Maybe a Pitts, redo the woodwork behind the spinner. Tri retracts ad a pound, approx? So, at 6.5 lbs (I was wrong by a pound in my earlier post) plus one is 7.5 lbs, area of 660 sq in, gives a wingloading of 26 oz/sq ft, up from 22.5. Very acceptable. Boy, it would be tight.