So I actually have a setup similar to this, but with a mini pc (m.2 to 6x sata adapter, each one connected to a 4tb ssd - well eventually, only 2 are populated currently) and I did use a dremmel to cut through the metal top of the case and it was still a horrible sharp mess, even after I tried sanding it down. I ended up 3d printing a custom i/o shield to stop my cables (or fingers) getting sliced on it and that actually works really well!