Either a Y cable hooked to CH2, one goes to the ESC (with brake disabled), the other goes to the brake servo. Will take some fiddling with the EPA and linkages to get it right. Or, use channel mixing on your radio so that CH3 is activated at the same time as CH2 using the throttle trigger. This is better because CH3 settings (EPA, trims, reversing) will be totally adjustable without affecting the throttle going to the ESC.
The picture looks right, except you are missing the brake servo wires.
