I made traffic light heads that are true to scale that can be fitted with SMD nano-LED's. I made them available via Shapeways. When you let me solder, it will end in disaster. But a German modeller by the nickname Loetboy made an excellent how-to for these lights. The traffic lights: http://shpws.me/HbTX The how-to in German: http://www.wawerko.de/spur-n-ampeln-bauen+5952.html The auto-translated how-to in english can be found here