I had a heck of a time trying to put a Hitec full size RX in this little bird so I gave up and put in a 2.4 RX, quite a bit smaller. I know I used up valuable space with my landing gear blocks and adding a steering servo. Also, I never could locate a suitable battery so I went with an experimental (for me at least) LiPo setup with a voltage regulator mounted in rear compartment wit switch and elevator servo. The 2 cell LiPo was small enough I was able to put most of it under the tank, I think it is an Electrifly 1100 MAH 7.4 Volt. I also added a home made servo saver to the little HS-55 for the nose steering. By using the Lipo and an HS-55 for throttle I was able to stay at 22 oz and change for final weight. I am intrigued with the Sloper idea from Bundubasher, these are neat little airplanes and i was thinking an electric version would be cool too. I am happy with how mine performs as is and might yet remove the fear to see if she is a bit faster. Mustang that is a great deal on that radio! I put some pics for reference, the red thing is the voltage regulator in the rear(very light btw). Good Lord! no idea why the pics are so huge! never had that problem before!