I have had this EPTOSSB50B Echo Board. I took it out of a Cobra 29 ltd classic a few years ago. And would like to install it into my RCI-2970n2 Transceiver. By looking up the model I see they were placed in the Galaxy DX33/44/66/77/88) radios. Would anyone have info on how to wire the Echo Board into an RCI-2970N2? 73,