I first feed the string into the center mains and then walk backwards to make them even length. I then clamp down these 2 center mains. Then I start doing the mains, but for the first couple, the clamps obstruct each other. I used to do one entire side of mains, and then the other side, so this was never an issue. When I try to do both halves simultaneously, the clamps obstruct each other in the center strings. Any remedy ?