[Mondial]

Looking at the last photo it looks like you may have replaced one of the paper caps with another paper cap. The pink tubular cap appears to be a Sangamo molded paper, in which case it is probably as bad as the waxed paper one you replaced. That specific one appears to be a coupling cap to the output tube grid and is very critical as to leakage, which could destroy the output tube, transformer, and more.

Those plastic molded paper caps haven't been made in 60 years and go bad by themselves from age. It would be a good idea to replace this cap, along with any others you may have installed like it with modern film caps.