Never mind on the control horn setup stuff. I wasn't thinking about the surface thickness. That rudder is pretty thick where the horn mounts, to the ratio is a lot closer than I first thought.

Anyway, I'm planning on putting a Saito 150 on mine. Got a pretty good deal on one, and since it weighs the same as the 120, it should work out fine. Rough calculations seem to make it come out around 9lbs 3oz.