Hi MIke:
Radio Futaba 617. Dual LiFe batteries, each 3200 mAh for flight surfaces. Dual switches (MIracle). One life battery 2100 mAh for ignition with Valley View kill switch. Hitec HS7955TG servos all around for flight surfaces, Hitec HS5625MG for the throttle. Servo mounting is stock per the book all around. I think the geometry of the twin aft elevator servos might be just a bit different, but then again the R90 is not a pattern plane.

m_gutzmer - that 3 blade Biela looks great!