Me too Umi. The mast lights are all grounded via the brass mast, the leds wired in pairs with a current limiting resistor. However all the other lights throughout the superstructure are wired in pairs, the resistor in the positive lead and all the negative leads coming together at one connector. So far there are 10 leds on the mast, 2 smleds inside the bridge. an led embedded in each of the bridge consoles (4) 2 stern lights, 6 inside the lower cabins, and two wired to p/s nav lights. I still have to fabricate and add 10 external companionway strip lights, from 1mm x 2mm smleds embedded in resin. All of these functions are on seperate switching circuitry, so they can be turned on individually.
I saw on one of your discussions on another forum, a switching unit that illuminated the leds in a very realistic way. Sadly it was from 2010 or thereabouts and search as I may, I have not been able to find if it ever progressed.