The servos do get mounted upside down with a low wing plane as compared to the way one would install servos in a typical high wing plane. Have your friend carefully study the layout of the inside of the fuse as to where to mount a couple of simple rails running from one side of the fuse to the other. The servos will mount onto these rails 3 abreast=elevator, rudder and throttle. I assume that a servo in the center of the wing controls ailerons so don't mount the servos in such a way as to interfere with the aileron torque rods. Set your motor on the mount and position forward enough to have the prop hub clear the front of the fuse nose by an eight of an inch or so. If you go to a flying club ask some of the guys there for help. Most fliers are more than delighted to share.