I've started to install braces to raise the center of my sagging roof. In the photos below, the Trailmanor is covered with ash from the California fires and in sore need of a bath. Here is roughly how the braces will work, with the pieces not yet installed:
Threaded shafts will extend to a sheet metal piece placed on the inside ceiling around the vent window openings, and pull up on that.
Here is how I am shaping the beams so that the cover won't snag on them. This was my first try without marking anything, cut with a fiber wheel, and smoothed with an angle grinder, sanding wheels, and a foam hand sanding block. Aluminum sands really well.