Correct motor
Jim,
See my post #4.With standard size servos and light weight engine you will be most happy. The instructions said they had a OS .40 FP in the prototype. I am not familiar with the TT .42 but if the only choices you have are listed I think this might be the one to go with. I don't know if the FP .35 has the guts The FX is way too much.
Sparky