The mystery is solved!

Thanks for the tips, suggestions, and lively discussion.
I was able to loosen and adjust all of the coil slugs in
the radio without breaking any. Belive me, fellas, that
radio was in sore need of alignment! Now that I have the
set functioning, I can continue with troubleshooting and
restoration.

Here's what I did to loosen the slugs:

1. denatured alcohol... no luck
2. non-acetone nail polish remover... no luck
3. acetone... yahoo!!!

After sitting for a couple of minutes, the acetone loosened
the sealer enough that I was able to break the slugs loose
with a plastic alignment tool (I apparently pushed someone's
buttons when I referred to that tool as a "diddle stick" in
an earlier post!). I removed the slugs, one at a time, and
cleaned all of the old sealer out of the threads. It looks
a lot like some kind of lacquer, which makes sense if I was
able to soften it with acetone.

Two of the coil forms had their internal threads factory
pre-stripped-out, so I had to use some melted wax to hold
the slugs in place in those coils.

Anyway, a big "73" to the guys who suggested acetone, 'cuz
your suggestion was ultimately the right one!

To those curious as to why I would even care enought to do
all of this work on an old CB radio, I have a very simple
answer: restoring ANY old radio is fun! What am I gonna
do with the finished product? Sell it, of course (likely
at a huge loss).

73,
Dean K5DH