This lab is the install.
Caution: Nothing should ever be forced. The minute you start "pushing" "pulling" "bending", you are just seconds away from damaging something or yourself. Most of these parts are delicate.
First:
Document the make and model of the mobo
Second: Provide a diagram of the location of the offsets for this mobo
Third: Place the offsets in the case. Please don't forget to do this!!!
Fourth: Place the bezel in the case. Please be careful with this razor sharp piece of metal.
Fifth: Verify the placement of the offsets and the bezel covers
Sixth: Install the mobo and screw it in place
Report all problems.