I was just about to warn against Pledge, but bandersen beat me to it. Silicone contamination is very bad news. You can't remove the silicone by stripping, or even by belt-sanding off all of the old finish. Stripping or sanding just spreads it around.
There are safe alternatives if you want to shine it up a little. Good old wax, for instance.
Congratulations on getting that interesting set. That model is still on my wish list.
Regards,
Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html