The ends of the nailers stuck out beyond the edge of the subfascia, which put the edge of the nailers above the roof plane. The height of the plumb line on the nailer where it overhangs the framing equals the amount the nailer needed to be “dropped” so that its inside top edge would be in plane to catch the roof sheathing.
A framing square was placed on the ledger and used to mark the location of the "jack rafters" on the nailers.
The template was used to lay out the profile of the angled corner posts, and the dimensions were transferred to a section of 2x4. For each post, a bevel was ripped on one side of a pair of 2x4s.
On site, after a new 1x4 bottom plate was nailed to the existing sole plate, the angled corner posts were toe-nalied to the plates.
The corners of the top wall plate bisected the angled lookouts. The wall was positioned, plumbed, and secured to the center ceiling joists.