Completely wrong sequence @3:37. That's the "Soul Survivor" pattern, or double-sequencer pattern, named after the one episode in which KITT's CPU is removed and the car is stolen. Randy (the hacker) creates a hacked CPU to control KITT's automobile functions, but the scanner operates in this double-sequencer pattern. The typical and "correct' pattern is for each LED to light sequentially from left to right, then back again. This sequence is not shown in your video. I was hoping to use this as a guide to build a functionally correct circuit, but I can't use this if the lights aren't going to operate in the desired pattern. If you're going to reference Knight Rider in your RU-vid video title, at least be faithful to what was actually in the show, please.
Use a relay board. One relay per motor. Here's one with 8 relays: www.amazon.com/Lystin-Channel-Control-Optocoupler-Raspberry/dp/B07R2J2V46/ref=sr_1_1_sspa