Supporting my odd boat


I have a cedar strip row boat (maker and year unknown) with the canvas off and the seats out.
She is quite tender with out the canvas and seats in place.
Just like a big basket.
At this point she is upside down and hung from the stern with a strap from the ceiling. The bow is on a saw horse where the cockpit ends and the decking begins, and the keel is supported with a 2x4 and a jack. I have two straps around the mid hugging the mid hull to add support.
She is just balancing in the correct shape.

I need some advice on a safe and easy way to support her so I can do the work.
A strong back seems like a good choice, but there are structural issues that make that less than straight forward. The gunwales are rounded over with strips. They arch in pinching the space in the cockpit.
The only flat on the top side is where the is where the sawhorse is supporting the bow.

Any suggestions?

Pictures at Row Boat/