Here is what I found: the headlight and warning light LEDs (on the locos that have warning lights) are surface mount LEDs directly attached to the nose PC board. Without really major micro PC board surgery, it isn't possible to separate these headlight LED circuits to control them separately. They are reached via the green and blue wires from the end of the PC board. The number board LEDs are on a separate circuit reached via a yellow and red wire coming from the side of the main PC board. You can control these separately via either the green or violet wire from a multi function decoder. However, you will need to connect the wire from the LEDs that you use for this via a resistor -- I used 560 ohm. Works via F2 now. Wish you could set up the warning light separately, and if someone figures this out, I'd like to hear it!
So you're a little better off with an E7 with just the upper headlight.
So you're a little better off with an E7 with just the upper headlight.