amazed at how dangerous this square d panel is

hi guys,
I was inspecting another 1950s house today in southern california.
In all my years as an IBEW Electrician and the 9 years I have been doing home inspections, I have never seen or dealt with this panel.
It is a square d model number: QO56MRO panel. This panel is original to the home I found it in, which is built in 1957.
As I was taking off the front panel cover of this unit, boom bang !! the cover shorted against the two main bus feeds which are completely open to the panel front.
Unbelievable construction of this panel.
What were they thinking ?
The two hot busses from the meter are exposed to the front cover as you are taking it off.

Just a warning to anyone that encounters this type of panel…It is dangerous in my opinion to even remove the cover.

Kevin Rea
AV Home Inspectors
Palmdale, Calif.