I'm not even sure that's what it's called. Inside the cavity on back, that piece of steel with teeth to hold the springs from the trem block. I always thought that it was supposed to be parallel to the edge of the hole (90 degrees to the strings) but a buddy just told me that it should be at a slight angle. It makes sense, seeing as how each string exerts a different amount of tension, but I don't even know whether there's more tension on the high or low strings. So, which way should it be angled? Tighter on the bass side or the treble side? How many degrees? How do you guys do it? I've got the screwdriver in my hand, but I need some expert input here. Thanks.