Joe, Rick and others,
Who is to say what is behind that cover?.
Who knows how well the wires have been tightened in the Disconnect?, Line or Load side.
Or, as I have come across before today, the cover was holding the Pan unit in place.
There are just so many variables and with Short-Circuit Fault Currents getting higher and higher, the need to isolate Live Panels, while not actually working on them, just opening them up, is fraught with danger these days.
If it will melt metal, just think about what it will do to your exposed skin.
It's like an un-controllable Arc Welder.