What you see is only the pre wire, there were 5 or six items required to complete the system $2,000 at least. Nothing is available any more and it was all ANALOG which will be dead Jan 08. OKI has been out of business, you might be able to adapt to the harness, I have not seen any schematics, there might be some info here. The RJ type connector would indicate it was Motorola, there ia also nothing available from them. In my 92 with an OKI the cables ended up in the rear drivers wheel well, the console cable ran up to the glove bin on the dash thru the control unit in the bin and back to the rear. In later years there was a cradle and handheld phone that interfaced.
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