I would be interested to know when Smartnav became a factory option.Many years ago at one of the national meets I met an elderly chap who had owned his very early car from new.If I remember correctly he was a former Longbridge worker.He told me that his Tm system was specified at new.
I have never seen this on any other 75 or ZT.As I mentioned above,it had a round Tm button on the dash.I can't remember seeing any other lights like the OP mentions.The switch location and shape should confirm if he has Smartnav.
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