GTF,
Measuring on the plans, the gap between the ailerons as cut is just over 8.6", so without altering anything you're down to an 8" prop -- you can trim a bit off the ailerons to make it work with a 9" prop . . . but . . .
First off, even a fast 8" prop is VERY under-propped for this motor on 3S. A 9x6 isn't bad but still would mean loosing ~1/4" off each aileron to work. Switching up to 4S would help, but still not ideal. This motor is SLOW for what you'd want for a pusher Versa.
Second, from taking with Josh, the Versa on this motor is VERY hard to get a good balance. It needs a LOT of weight forward to counterbalance that motor, making the wing very heavy overall. This motor is HEAVY for what you'd want for a pusher Versa.
Tractor is fine on both points -- no restriction on prop length, and the motor weight will work in your favor for balance.
All that being said . . . it can be made to work, but what you will have to do is build the airframe LIGHT (most of the airframe's surface is aft of the ideal CG), notch out the ailerons to go with a 9x6", move your battery as far forward as you can -- 3S 2200's or bigger, but that will be hard to fit -- and BALLAST.
I've made a pusher versa with a slightly ligher, slightly faster motor, with a 3S2200 just north of the CG, but ended up needed to add around a 1/3 lb of lead to the nose, just to get the balance . . . and that's with a motor about 3/4 the weight. Make no mistake, she flew well, but she was also VERY hard to launch and flew VERY heavy.
Lighter/faster motor means less ballast and lighter/faster/easier to fly Versa.
