We at first were considering just replacing the roof and a bit of the right rear quarter panel.  After looking closely though, we discovered that there was more damage than we had thought.  Until we got the car home and looked closer, it wasn't obvious that there was additional damage that would be difficult to repair properly with a simple "roof swap".  There was hidden damage to the right side "B" pillar (rear door jamb) that would have been difficult to repair properly in addition to the obvious damage to the rear quarter window and grill area.  There was also some damage to the left side quarter window that would have been outside the roof swap area, requiring even more time to repair.  For these reasons, we elected to do a "roof and back half" replacement.  This choice simplifies our task; there will only be 2 cosmetic areas to body work (the front window frame joints to the new roof).  The other joints will be in the "rocker panel" areas near the rear edges of the doors - they won't be visible with the doors closed.

We spent some time considering the best way to cut the old body off the car; we wanted to preserve the "shelf" area as much as possible so that we would be able to use it to attach the new body parts to - and the shelf also partially supports our fuel cell.