At first, I just tried the remains of a few eggshells with residue still in them- but that didn't produce enough sulfur dioxide. So I went and cracked an entire egg into a plastic grocery bag, tied it loosely, placed the package on top of the rod sections (I left them out of the sock), put the lid on the case, and let nature take its course. It took around 6 weeks, but at the end of it, when I removed the rod sections and fitted them together, the fit and suction was superb. As good as the most well-lapped ferrules on a new rod.
The ferrules are grayish from discoloration, of course, and I could polish the exterior of the female if I wanted to. But they don't look that bad to me in that condition. They just look "vintage."
As for the rotten egg, I just tossed the bag out. It smelled like you'd expect, but I actually had the rod tube in my living quarters while the experiment was going on, and I only noticed a problem with the rotten egg smelling foul after I removed the lid (one of those cheap LL Bean green plastic rod tubes.)

