The installation of the support angle on the fuselage requires some thinking to take the measurments. Here is my setup. Once everything is clamped, the drilling is done in incremental steps to 1/4".



After the frame is installed, the upper brace is clecoed in position and all the drilling is done.



After a last height adjustement of the frame (my cut last time was a bit shy), I drilled the frame to the support angle. I still have to drill the inner holes and countersink where it is needed.