If you have a modern tug then a white LED would be appropriate because of the blue/white light. If you have an older tug then I like using the lamp modules/reflector from the Pelican brand flashlights, specifically the module from the Mitylite 2AAA flashlight. It has a Xenon bulb that puts out about 6000 candlepower and runs off of 3 volts. The modules are 1/2" in diameter and I shorten them up. They cost less than $5.00 each and can be found at better sporting goods stores or at Grainger. As for a housing, I make them up out of tubing and plastic pieces. Good luck.