[MrFixr55]

+1 on Arran's comments.  Best thing to do is the following:

• Move the power switch from the neutral (chassis ground, B-, 1st AF Heater and cathode) to the hot side (Rectifier plate and /or heater).  there will usually be a connaction between the power switch and one end of the volume pot.  Be sure to remove this and connect the Volume pot to the common B- (See next step)
  
• If possible, create a B- and heater return ground "Mecca" separate from the chassis.  Move the "neutral" conductor of the power cord and all chassis ground connections except the tuning condenser to this isolated Mecca.  Connect a 0.1uF cap between this Mecca and the chassis.  This duplicates the "warm chassis" as opposed to the Hot Chassis.
  
• Install a polarized power cord or if the power cord and plug are original and you want to keep it, widen the prong connected to the "Neutral " conductor (the one connected to the above mentioned "Mecca")
  

These steps will eliminate a common problem with sets of this vintage where there is always a danger of the chassis being "hot" or "warm" connect to hot through a capacitor depending on whether the switch is on or off and the direction that the power cord is connected.

Ther is somewhere an article on making this mod, possibly in Phil's Old Radios.  If I find it, I will link it.