I reinstalled the guard again this morning and set it so it juts straight out parallel to the roof with the plan to slowly lower it incrementally over the course of the day. The hinge is tight enough to do this. She was sitting the nest this morning just before I reinstalled the guard.
My other nest now also has 4 eggs this morning. That one has a sparrow spooker on it as it’s located in a significant sparrow area. I’ll go ahead and install one on the box in nearer the woods that I’m trying to get the guard installed on. I’ll try to put a wren guard on the other box today.
Thanks for all the excellent advice. This whole endeavor puts the old saying “don’t count your chickens before they hatch” in a new light.