It should be understood that the following measurements are approximate as the shape of the box changes from front to back and side to side. Try measuring an Eggplant.
The back of the box measures 3 & 1/2 inches high X 5 & 3/4 inches wide
The front measures 6 & 5/8ths X 4 inches at the center for each measurement
The length of the top is 10 & 5/8ths inches at the center
The length of the bottom is 11 & 5/16ths inches at the center
The length of each side is 11 inches at the center
The left side is 3 & 1/2 inches high at the back and 4 & 1/2 at the front
The right side is 3 & 1/2 inches at the back and 3 inches at the front.
Does this sound confusing? That's because the back of the "box" is a true rectangle with straight sides and right angle corners, the front is not square and not rectangular, it has round corners and unequal length sides. Hope pictures will help.
Yup the hardware is not correct, just there to hold it together, have to glue in the lining, then rivet it.
The picture in the OP is a Brookville reproduction. The back panel of the reproduction is better executed, but spot welded not riveted, the corners are round whereas an original has square corners. The 4 sides of the Brookville are better formed because they follow the shape of the back panel, but the seam is welded not riveted as original.
One last comment, yes my firewall and body are bolted down on the frame AND the glove box is free range at present.