[MBZ] Idle curiousity about the CHMSL

[David Brodbeck]

My '83 300D Turbo has a CHMSL, also known as a "3rd brake light."  It
looks kind of tacked on and generally un-German, to me.  Was this
something someone added at a later date, or were they coming with them
already in '83?  The wiring is tapped off the left brake lamp.