<<<BACKto the blue MOTS guitar's listing & description.
By fraying the end of a stranded wire, I made a new strings grounding
wire between the hand cover & pots; Linking the hand cover to ground.
Here is a TYPICAL mid-late 1950s Magnatone wiring;
Not neccessarily factory standard for the 1947 Magnatone of these webpages, .....nor other models and years. For techs: Notice this wiring is functionally the same as most Magnatones EXCEPT that the volume pot here acts as a balance control to regulate amounts of ground between the volume function (grounds the signal) and the tone function. When a resistor is in a Magnatone circuit it is typically band-coded red, black, orange = 20K ohms.
Now back to the blue MOTS Maggie:
Wiring was not changed; It was functional; It is likely the factory wiring scheme; But I've not sure about the circuit's resistor being original; Value is unknown and I'm not going to chance tearing something by trying to remove the tape and look; (But I'll bet the masking tape is cost saving insulator for a bare connection between the cap and resistor ! ).
The resistor, when present, is in series in the capacitor line between the tone and volume pots.
Typical 1940s to 1955 Magnatone lap steels: Pots = Clarostat, code 140_ _ _, and caps .05 mfd.
Here is a 1950 MOTS Magnatone lap steel schematic. Notice that the volume pot does not "throttle" signal passing through it, but is a variable resistor to regulate grounding the pickup to control the volume, in the same manner a tone pot works except without the filter capacitor; And why a shorted capacitor in a tone circuit acts like a volume control ! A capacitor that is 'open' in a tone circuit simply opens the circuit and disables the the tone circuit.