I once put plastic letters inside the tail lights of a friend’s Trans Am. The 80's T/A (knight rider years) had a giant light bar that included parking , stop, and turn signals. He wanted to personalize his new white / silver toy by displaying something unique. So, he bought some of those acrylic sheet letters that typically display movie times on lighted signs, then asked me to install them. I looked at as a challenge and hey... not my car. What did he want spelled out every time he braked?