And also, how well will the old power transformer hold up with increased peak current surges? Frankly, I would not replace the tube with ss diodes, but would add a small light bulb in series with each plate lead as a quick blow fuse. I think Zenith at the time recommended #47 bulbs.
jr
here is the old thread where that is recommended:
http://www.videokarma.org/showthread.php?t=265632
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