Definitely knew this was mandatory as of 1986 on every car in the USA. I remember the third brake light on the 911 Porsche looked like “ET” also the Chevy Camaro looked like a last minute add.
Thanks for your feedback.
After all these years , do you still have the same GN , TR ??
For the 1986 Model Year, the Federal Rule was the addition of the Center High Mount Stop Lamp, or 3rd Brake Light. Most companies rambled to scab something on the cars, and most were poorly integrated. Even the 1986 Regal, it was a pedestal housing, placed on the parcel shelf. Not very clean, but okay compared to the 1986 Camaro and Firebird, but nowhere as clean as the 1986 Corvette.
Regarding my own Buick, if the question was directed towards me, no - I sold it over 20 years ago, but looking again...
https://turbobuick.com/threads/new-member-had-an-87-gn-looking-to-buy-an-87-tr.457094/