I have a new DCC ready E7 loco. I would like to install a Digitrax DH166 to be able to control the various light functions -- headlight, Mars light, and numberboards -- separately. Testing it on DC, I see that the default is for all LEDs to be lit. It looks like I will need to identify the wires going to the LEDs, cut them, and splice them into the corresonding wires coming out of the DH166. However, the wires on the loco are colored blue, green, and yellow, and I'm not sure how they correspond to the white, violet, and green wires coming out of the DH166. Has anyone worked this out? I can experiment, cut the wires on the loco, and see what happens, but if someone already has this figured out, I'd like to learn it. Thanks!