I have made a holder to mount a small 12v LED strip on the Anycubic Kossel Delta Linear Plus.
This uses the standard mounting points and bolts that hold the screen assembly onto the baes of the printer.
In this example, I have used a standard 12v dc cool white LED strip sourced from a local electronics store that can be cut to length. I am using 10cm, although 5-8cm may turn out neater and with a little bit less glare. The LED Strip is backed with 3M adhesive, and sticks to the holder nicely.
There is a spare 12v port on the control board. The connector type is a "2pin JST XH connector". Google this to find the plug you need. It is commonly found on fans and other components. Or you could easily (carefully) solder your LED strip to the under side of the board onto these pins.