This weekend, Charlene and I got the layer of 5/8" firebreak drywall on outside of the sheathing. Screwed on, 2½" screws at 6" centers on the outside, 12" centers interior.
Then we wrapped the building with housewrap (leaving the western wall flopping so that it can be inspected, because it's the side within 5' of the property line and therefore must be at least a 1 hour firewall. Aside from the sheathing, the wall we've got is basically a standard UL 2 hour firewall. Overdoing it is our way.
Anyway, got the housewrap on, installed the windows. Then I realized that I'd left some shipping parts on the window, so I pulled them out, removed the parts, and reinstalled and reflashed.
The door is started, and we're working on the electrical. I pick up the trim pieces today, so I can start running siding tomorrow.