Hi All,
Your local TV repair man should know, or he couldn't be bothered
doing it for you.

3 wires, one should be red, one should be white and the other will either be
a braid, or black.

black / braid = ground, connect this one to the rear section of the new
phono jack

red = right signal, goes to middle section of the phono jack connector

white = left, goes to the tip of the phono connector

maybe the tip is right and the middle section is left, but armed with this
info you should be able to resolve it now for yourself.

Just one handy hint, have the amp off when you are ready to test the
headphones, and at minimum volume. Plug in the headphones, turn on the amp
and slowly turn up the volume to around 1/4 of the way, if you hear nothing,
something is really not right and use balance to check that left and right
are correct.

Paul