That image does not really help much as it is not descriptive of what
we would really see when the back is off the tv set.

In any case I think that is the chassis that has a row of regulators
along the center of the main board and those get bad solder
connections. Some are difficult to get at without completely removing
the board.

Add solder connection problems in the if can and tuner, as well as to
the Y-delay line.

Still may be best to find someone with lots of experience on the older
XBR Sony models as they will know the problem areas once inside the set.