I want to interface my Icom IC-706 M II G to my alpha 9500 amplifier. I have the OPC-599 adapter cable c/w an eight pin male plug to into the ACC2 connector. Which option should I use on ACC2, pin #3 Hsend or pin #6 Vsend and can I safely use that without anything else in line? 73 from Fern VE7GZ