Yes, I can absolutely wait until tomorrow.
I vote we stick with 15 degrees unless we can find conclusive evidence that 10 is better.
I actually re-built my frame using all glue and screw joints yesterday to begin testing
I thought the glue and screw technique was a little harder to put together than with the bolts, but glue and screw required fewer tools (the bolts would require that everyone have an imperial socket set because we can’t get metric bolts in time).
My biggest concern was that rotating the top bar would make it weaker, and so I did some testing running the machine from the very bottom to the very top while filming the end of the beam next to a tape-measure. I didn’t see any overall flexing, but it is a little springy, while it was rock solid in the other orientation. My supports are 22 inches from the end of the beam, so reducing that to 12 should help significantly. Here’s a video of the end of the beam sped up 15x to make the movements more obvious: