How to unscrew prehistoric fuse box? ...

I a short time ago have my septic...
More info needed!!!! unscrew from what?
what type?ETC.

How do I move a door process to...
First and fore-most SHUT OFF THE POWER to that fuse box.

Fasteners or screw removed, then disconnect, later cap wires percode.

If you are not following this contact a licensed electrician for your own sanctuary.
What is the effect of using a microwave...
Answers:    If you are actually trying to remove the infirm fuse box..turning the main breaker bad wont do alot for you, for the incoming wires from the electrical poles are still hot as ever!...This would be a job for an electrician