I watched the video by Christopher Schlegel on how to restring. But I noticed my guitar Yamaha Pac012 has something on it his guitar did not, not sure what it's called but it's a small piece of metal on the headstock that the 1st and 2nd strings run under. So I'm confused about how much slack to give. I don't know if his rule of string to two pegs applies here or not for length. I'll try to upload picture to show what I mean by silver piece.