This is what we improvised for a new route. It starts on the dihedral until you get about 7' below the roof, and then crosses west (climber's right) over to the 5.7 arete and face by means of some positive handholds. Changing corners from dihedral to arete/face is the crux, 5.8. Once on the face, continue on the arete (climber's left) or climb the face toward the right up to the top. You can climb over the top from there toward the TR/anchors, but you have to climb over the rope. Lowering requires dropping back over the arete, or lowering down the right face to a ledge or down to the dirt, although the rope pulls you over to the fall line (towards the dihedral).
Toprope - We used long (10') slings to set up a TR that drops down over the dihedral - the rope can be managed from there without drag/damage. You can lead the dihedral and set trad gear, but once on the face to the west, there are few places for protection.