Spektrum DX6i and AR6200 - Aux 1 input setup

[Eventorizon]

Does anyone know how to get the Aux 1 output on the AR6200 reciever to be activated by one of the switches on the transmitter? I have read the manual of both from cover to cover and naught.

I have me steering linked to ELEV and AILE, GEAR is my weapon on/off and I need the AUX 1 to flip my forward and reverse with a special mixer I got from the US (IMX-1 Tank Mixer)