im looking for the third brake light for my 1986 300sdl. its dark brown interior. does any know where i can get one, preferably an after market new one

 

Generic ones used to be sold by the regular auto part stores or place like JC Whitney&co.

Oddly in 3 years of hanging out on Mercedes Forums I have not read of anyon adding one. But, it is a practical idea.

I added a generic one to my Volvo back in 92.

You might do an internet search of the online parts places that specialize in Merceds interior, body and Wheels to dress up Mercedes.