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Marty,
Just a little tip on paper caps and the criticality of leakage. The most critical is a grid coupling cap feeding G1 of a power stage from the plate of a preceding stage. Because the plate is positive, any leakage of DC thru the cap will drive the power tube's grid more positive, causing the tube to overconduct. Since power tubes already run hot, thay have little 'headroom' for overcurrent.
In your set, the most critical coupling caps (in descending order) would be C178, feeding the grid of the 6BG6.
C157, feeding the grid of the vert output
C208, feeding the grid of the audio output
then the four caps in the video chain mentioned earlier
then any bypass caps along a B+ line or on a tube's screen grid (G2). And any bypass caps along the AGC (or 'picture control') line.
lastly, any bypass caps having a low resistance in parallel, such as a cathode bypass.
So if you elect to replace caps in batches, that's a general guideline that'd apply to other sets as well.
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