It would be better to put a nice new service panel in where that old safety switch is- it's for the screw-in fuse panel,(all 30 amp fuses on 20 amp circuits). I could have breakers! Get everything grounded! I have some conduit with extension cord in it. The conduit is held up by tying the cord off to other conduit and with coat hangers. This all is in a dyno room where engines are tested-all kinds of flammable stuff around.
Frank