"One for the reciever (4 AAA) and one for the motor? Where should I mount the reciever batteries?"

No, no, no, no! You do not need receiver batteries, since your ESC comes with its own BEC (Batttery Eliminator Circuit), and it diverts current (at 8.4v or 9.6v) to the Wingo's motor, AND to the Rx and servos (at 4-5v). All you need is the 7 or 8-cell flight battery (2/3AA KAN 650's would be ideal - don't be suckered into buying AAA packs for the Wingo, since its 400 motor needs 8-10A, which AAA's can't supply!).

Cheers, Phil