in the linkI had the KMP skymaster done as a O-2 and loved it.. getting the Hostetler plans for a larger one, will build a quick and dirty fuselage to mockup a set of retracks for this bird. found a build from over the pond of a guy that built his own.. lots of pictures, very cool.. the thing had gear doors from hell. alot of the full size birds had the geardoors removed. but it did look cool with working geardoors, i have a few months before begaining.. doing a Vailiy 1/4 Cessna birdog right now.. power is Rimfire 65cc on 12 cells.. the Hostetler 337 would be electric also.. this guy in the link below built his with retracts been trying to contact him for information..
http://www.youtube.com/watch?v=hcx7oUn93EM
another good video
http://vimeo.com/12402285