Picked up a 1/5 scale 72" Waco biplane and need advice on engine selection. Two engines available but both will require modification to airframe. 1-Quadra-35 / 18x6-10 prop. 2- RCV 120 / 18x12 prop. Which of these engines will give the best performance on this plane, when painted and finished out, should weigh in at about 12-13 lbs?