In regard to ground stakes, this is preachin' to the choir for sure here, but can't be sed often enough.
Always re-flow the ground stakes on the far right end of the chroma board. Although not related to the color sync problem, when these two go open (and they will
!), it kills the heaters on the 6GU7s.
When that happens there's a cascade of unsavory events.
The 6GU7s' plates go 'waay positive, driving the CRT grids positive (since they're direct coupled). CRT beam current goes into avalanche, lugging the HV down. Picture blooms, goes out of focus and then fades out. Yet the 3A3, flyback, and 6JE6 are still getting hammered with overcurrent and overheating. If you don't catch it in time it can be a real meltdown... just because of those 6GU7s' heaters going out.
This ground stake problem was endemic in the CTC-15, 16, 17 and 25 before being corrected.