When changing strings, is it best one at a time, or all at once? Also do you wind all the excess string up, or just a few turns? I changed one string for my brother, and I didn't get many turns or wraps around the tuner knob thingy and I kinda regret it. Should I wrap as much as I can, or just a few, or does it really matter? Also, the bridge (near or on the tremelo) , they all have a height adjustment w little hex key screws. Are these preset,does everyone have there own setting, does it affect much, or what? someone please shed me some light with this one!!