Thanks, I'll post pictures of the radio and the booklets. This booklet always had these small keys, so maybe someone can tell me what they were for. So here is a little history on the car, which we do not have any longer: My father purchased it from a Catholic Priest, military, Germany. He purchased in 1966 from priest and my father picked it up at customs in LA. Price was like $1,900. Unfortunately we threw away the euro lights back in the 1970's. It did have headrest. I remember my family putting on over 350,000 miles on that 190. It was an excellent dependable car. Not much for speed.