[Arran]

Just to make it more confusing here is another model 91 schematic that doesn't show parts with dotted lines in that spot, but shows parts with dotted lines in another spot. https://philcoradio.com/library/index.ph...chematics/ . Does your set have a code number?
Getting back to the power cord I suppose you could add a fuse in series with one leg of the power transformer primary, use a fuse block rated for 120 volts, that you can anchor to the chassis, and not an automotive fuse holder. There was a guy on Y.T that used the latter years ago, he used these clunky plastic inline fuse holders with thick pigtails attached, which were never rated for mains voltage, not to mention they looked stupid. If I ever ran into that in a radio it would be clipped out and tossed.
Regards
Arran