[Mondial]

Are you sure you need to change the cathode bypass cap? There is very little voltage across it and unless you are positive that it is open or intermittent I would just as well leave it alone. It is not in a circuit location where failure would do any damage and DC leakage is not an issue.

Typically I do not replace cathode or filament bypass caps unless they definitely check bad or otherwise have to remove them to replace other parts.