[morzh]

Ed

Impressive effort with transformers, I still outsource mine - hate the job. My rewind exercises are limited to RF coils, preferably without criss-cross winding.

As for the caps, a single cap could be possibly recovered if shows no signs of leakage for which you have to use a real cap tester that does test leakage at high voltage or a Megger, which does same. However, with the recovered paper cap being, well, a paper cap, it is a matter of time (and, if one is not hit by a bus untimely, well within one decade so even an old fart has a chance to see it happen) before it is to its old tricks again.
With the tar block - how do you intend to bake a tar block? it is potted. With a tubular cap porous paper makes the vapor escape possible, but with the block it is entirely different matter.
AMAF the block might still work, the caps' leakage if small does not mean a whole lot, and the tar prevents a lot of moisture entrapment. However you will find out the caps are out of spec, often 100% so. It might matter or it might not.