Three weeks behind schedule but no less satisfying, the roof is on!
I had to splurge and buy ten dollars worth of sheet metal roofing fasteners for this job. They have sharp ends like nails to puncture the sheet metal, threads like screws to turn into the wood and hex heads like bolts so you can use a wrench to tighten them. I put about seventy of these little guys into the roof. Below you can see the green heads of the fasteners. They also have a neoprene washer that seals up the hole as you tighten them.
I know hand split shakes would have been much more authentic but I kinda dig the 1930's depression era grunge look of the sheet metal.