Take an LED and cut off the legs, file the bottom flat and file the ridge that is around the base of the LED off. Drill out the LED to take a GOR 12v lamp.
Take some brass tubing that is a good fit over the LED and solder a small brass washer to one end of it, clean off all the solder and polish the end of the tube that has the washer on. Cut the tube about 3mm from the washer and clean off the cut end.
Push the small bit of tube over the LED so the washer is flush with the base of the LED, insert the 12v GOR into the hole drilled in the LED, if required, superglue the whole lot together.
Makes a nice bright light