3.3 kΩ resistors, one per LED, are soldered to the common (corresponding to the blue wire of the decoder) near the PCB diodes (9). The other end of resistors is soldered to a copper pad which has been split in two (6) and (7), to which the blue wires are connected, the back LED’s one (6) and the front LED’s one (7). The green wire is soldered to the side of the corresponding tulip pin of the decoder connector (4). The white and yellow wires are soldered to the corresponding pads. The violet wire is connected directly to the decoder’s one, thus without passing through the PCB, and is insulated with a heat shrink sleeve.