I had the bright idea

Haha, I enjoyed that. Although you’re pursuing using parts from a flashlight, I wish to point out that LEDs are now fairly straightforward to put together into a full lighting solution. Generally, it would be an LED module, an optic, and the driver circuit. Maybe a heatsink too. Ok, maybe this is somewhat complicated lol

I’m not affiliated with that supplier, but I’ve bought from them before to build a custom headlight for a bicycle.