Basic top bar mount for the cheap and super bright Eagle Eye LED:
https://www.amazon.com/gp/product/B00MVMRS6O

These are 12v LEDs. Two can be connected in series ( red/+ to black/- ) and powered directly from the printer 24v PSU

WARNING
These suckers get really hot quick! I added several washers, as many as it fit, of different sizes acting as a radiator to manage. See image.

V2: Simplified and cleaned up geometry a bit

Creality

Ender 3

No

Yes

.2

20%

I printed it sideways with supports, was easy to clean and use.