These are mostly fixed in luxury cars back in the days. I will share more updates after done up cleaning and testing.
Nice find, I can't even imagine seeing one of those in a local junkyard. I remember seeing installed versions, they were the fashizzle back then.
Discovered these from an old accessories shop, car audio business was at their peak in the 80s. Now in total run down condition and offers only misc services. The shopkeeper went into the junk room to retrieve these gems. He will soon cease business for retirement.