Rear third eye tail light

I'm looking into a used SL 500, what was the first year (in the 90's anyways) did MBZ put the third tail light in the center of the trunk lid?

This would be the flush mounted version.

Bump.....

1986...It was manditory for all cars made for US had to have the third brake light by 1986. For 129 cars the brake light location is the same no matter what year.