Workrooms often don't get to see their work in a truly finished room.
Often when we go to measure, the room is still under construction, like this one.
The shade needed barely 1/4" off one side of the board. The fabric fit just fine.
Well, we are nothing if not problem-solvers, and Mario's improv experience serves him well in all phases of his life. He wielded the saw, and I helped by applying my weight to the miter box. A little hot glue and a couple of screws later, that shade was hangable.