[MrFixr55]

Interesting power cord wiring. Scary thing is, if the GTR 19 Schematic on NA is correct, the chassis u\is hot, not through a cap and resistor, but directly hot. And, of course, the "neutral", not the "hot" is what is switched, so no matter how it 1s plugged in, one stands the danger of getting bit real hard. Likely why someone made that back. My SOP for these radios is to change the wiring so that the switch is on the hot side, the chassis on the neutral side, preferably through a 0.5 uF cap and 250 K Ohm resistor between the chassis and a "Mecca" B- and install a polarized cord.

Is that screw terminal the antenna input or is it a Phono input?

How to fix the stripped thread depends on many factors. What is the size of the current set screw" Go up one size, drill and tap. If it is 8-32, you may be able to drill the hole out and tap for a 10-32. If the knob is deep enough, a 10-32 Allen set screw will work fine, otherwise you will have to cut down from a regular screw and notch the cut end to accept a screwdriver. There is a product called a Helicoil insert for restoring threads. They are commonly used on car engines when a spark plug port is stripped, but I don't think that they make small Helicoil inserts needed for this knob.