After more tracing and meditation, I believe that I have found the answer to my questions above.
C25 was never grounded like the other can caps to begin with. It was mounted isolated from the chassis on its’ board which was riveted to the chassis. It was wired to C26a/b which was grounded.
On the new C26a I ran a 600v wire from the common lug to a new ground terminal I installed. R62 used to run to the grounded twist tab. I re-routed that to the same new ground terminal.
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Then the C26b 47 uf axial’s negative lead also goes to the new ground terminal. I also swapped out R62, R74, & R79-82 to the new higher wattage ones in the kit (those worried me because of my color blindness, but it actually was a breeze since I know how to use my DMM testing the old resistor’s values to verify).
There’s not a lot of clearance there, but it fits.
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