So if i understanding your post correctly, you connected a regulator to the meter lights blue wire and now your getting the dimming of the headlight and back running light when applying either brake? This is with all correct and working bulbs in place.

So, it is yet to be determined EXACTLY which wire I am connected to due to the JAPAN SPEC wiring is different and I have not been able to translate the wiring diagram, however I tapped into what I think is the light blue wire coming from the headlight switch, the reason I am quite certain, is that it connects to a "block" that does contain the dark blue wires that go to the gauges. I was not having this current problem when running regulator directly off stator yellow wire.

All bulbs are in place and working, but all the gauge bulbs are blown. I will replace them as soon as I verify what type they are by removing them. Should be same as usa but I am not going to guess at this point.