[Arran]

I believe that falcon is right, it's the acetic acid used in things like bathtub caulking that's the issue, it has a noticeable vinegar smell, however I found out that Permatex windshield and glass adhesive does not have acetic acid so it's safe, there may be others that are as well. But getting back to the Bakelite blocks, it isn't necessary to repot those, the new caps are already weather tight. I don't know how much dust would get into them considering that they are under a chassis, which either has a bottom plate or is screwed down to a board, the underside of a chassis is usually the cleanest part of the radio unless a rodent got in there somehow.
Regards
Arran