I have the model b DigiSpark, and need to cut the trace to the led. I have repeatedly scraped my knife across the white rectangle, and even rotated my knife some to dig deeper, and nothing! The LED still lights up! Do I need to cut a full hole trough the board?? I searched my board for "rev2" and it is not there! I know this is a model b! What do I need to do?? I tried to attach a picture, but can't get a non-blurry one.... I am kinda new to all this stuff, so I'd be nice if you could dumb it down a little for me... lol, thanks!!