In 2018, I made a custom shifter for my car at the Quinebaug Valley Community College Engineering Laboratory. The manufacturing center tapped a 15mm diameter steel cylinder for me, then I 3D printed a housing around it with space for a WS2812B strip and the two reflective acrylic surfaces which I designed and laser cut in the lab. I drilled a hole in my center console and fed a USB cord through it, which I split and soldered as a power supply directly into the ATmega328/WS2812B assembly.
The good news is that it lasted 50,000 miles without breaking. The bad news is that I have long lost the SolidWorks files for the housing and the vectors file for cutting the acrylic. However, with all this free time, I completely redid the electronics and the code, so you can make the guts for yourself with the new features.
New features: Photoresistor to dim at night (I had to unplug the USB from the cigarette lighter before), and a much prettier light display.
So this is what it looks like with the two way mirrored acrylic removed. A few notes in the construction. Make sure you have the same thickness acrylic, and cut the pieces so they are seated against the white box housing for the actual lights. That means the piece on top is going to be inset by the thickness of the resistors on the strip.