I used an Anduril driver from China. The driver was 32mm so I had to file it to 30mm.
I connected the leds with cables between them and obviously also to the driver. I had only very small copper vias to connect the cables so I used some copper tape with Kapton tape underneath to solder the cables. It was very finicky.
You might notice that I used only two centering rings instead of four. That is because the soldering close to the leds was to tall and would allow the centering rings to fit.
After assembly and a bit of troubleshooting the flashlight is up and running. 
