A mix of fine sand, vinyl glue and acrylic paint (no water)
In the beginning I just though to put the lights in the base and... wrong. Epic fail at the first test, so I has been forced to build my own spotlights using brass and drink straws. Looks cheap but work perfectly, especially when painted. After several test I built a version of 15 cm, it was the first time for me and has been a very slow and frustrating process to set up the lights, two mounths during the weekends.
Wiring a Kenner Jawa, just open the head and replace the original light with a new one. I just used a black tape for masking the original eyes.