Has anyone had any experience with the Circuitron MARS lamp kits? It looks like they come in a two bulb and single bulb configurations using 2.4-3V DC. I'm trying to find a single bulb option that gives a good MARS effect without having to do precision soldering to PCBs. These are labeled for HO scale but I don't see why they wouldn't work on O scale. At 3v, where would be best to wire these for power?