I've had a Williams Taxi Pinball in my collection for a while now. It's been a labor of love as it was in bad shape when I got it. Over time, I've been able to fully restore and repair it, and the last problem I had was there was no general illumination (GI) on the backbox. After much searching for a solution to the problem, I finally found enough information across multiple articles on possible solutions that I was able to track down and fix this issue. I took a video of the process to locate and repair this problem, and I've posted the video on youtube. I hope this helps anyone else that might have a Williams System 11b game with a similar problem.
Video can be found here: