At the 5th bolt you will encounter the 'phallus', 'the Bone of Stone', call it what you will, it's a cool chunk of rock jammed in a deep crevice.  Whatever you call it, it's not going anywhere anytime soon (we all hope), so go ahead and yard on it.  For Bisector you are going left and staying to the left to reach the smaller folded dihedral. Head straight up from the junction. This finish is balancy and tough.

In the far back of the Island Area at the far right side of The Tunnel Wall.  Go up the rocky ledges to find the rightmost line of bolts before you get up to the big 'V' notch.  This is the start for both Bisector and Illegal Dihedral.