Sounds like a cool project but I do not know about the drywall. You
will be mounting steel strips to the inside of the door, getting them
flush mounted and having them look nice will be a task. I am sure the
dges of your drywall will get damaged over time. Are you using drywall
on the edges also, mainly the edge opposite the hinged edge? How you
planning on creating a smooth transition between the drywall and 2x4
edge?