Fisher 500B Questions

I have a 500B that performs overall very well, but has two issues I would like to correct if not too difficult.

-The on/off/volume control only works in the volume mode; apparently not too uncommon on this receiver; I have seen the on/off switch on E-Bay for about $20 that apparently installs on the back of the volume pot; anyone ever install one of these?

-The right channel is louder than the left causing me to put the balance control at around the 9:30 position resulting in a little loss of overall output. I tried tube swapping to no avail; could this issue be tied to the volume control knob?

mine is doing the same thing with right channel louder, I found that if I put the bass control fully counterclockwise then the channels are about balanced. I am suspecting issues with the tone control circuit.... if yours does the same thing, would like to know.

I did not replace my volume switch, I plugged mine into an external junction box with a separate switch and never use my volume switch to turn the fisher on or off.
The 500B is notorious for the volume control not tracking properly and power switch problems. I've replaced many of them!