Sometimes simply putting a tiny front bead into place works for a gun shooting low.
The shooter has a tendency to bring the muzzle up a bit higher. Same as if a rifle front sight was too short, it shoots too high. Something you need in this case.
Doesn't always work. Depends on the shooter, his/her style, sight picture (or not!) ect.
Worth a try. Maybe try it on clay birds w/o a bead at all and see if you naturally point it a bit higher.
Just a thought before the bending process begins.