With Julie's help I got the stiffeners on the bottom skin and the entire right skin riveted. I back riveted 98% of the rivets. The left side will be a bit more of a challenge and I'm certain I won't have the opportunity to back rivet as much.
Began riveting the bottom stiffeners
Next I riveted the right stiffeners and bulkheads
I reassembled the left skin and will rivet it next