How do I operate the sparking control panel?

Hint 1 of 6:

I think you need a hand with this puzzle.

Hint 2 of 6:

Literally.

Hint 3 of 6:

There's a severed hand along the inner wall of this hallway, just next to the
control panel.

Hint 4 of 6:

But you need to get it out of its case first.

Hint 5 of 6:

There's something in the adjacent room that will help you here.