The stick was missing the upper E-clip, and the spring was bent from someone grabbing the rounded actuator bushing with a pliers and twisting it counterclockwise, which unwound the spring.
Everything got a vinegar soak, cleaning, and polishing. The vinegar will dissolve rust from steel like this, all the way down until all that is left is the pitted metal (which I then hit with some Simichrome polish.)
The shaft and knob got a drill sanding and polish, and I was able to break the glue on the knob with some heat, so it would unscrew. Also, the small parts got wet and dry trips through the tumbler, and I replaced the missing E-clip.
I was also able to salvage the spring by coaxing it back into shape.
The first pic shows the trick to getting these apart. You have to remove the E-clip that is between the lower roller and the rounded bushing that sits above it. That allows you to push BOTH the roller and the bushing back toward the spring, exposing the hidden crescent clip that is inside the roller. Assembly is the same, but in reverse. Compress both the roller and bushing toward the spring, install the crescent clip inside the roller, then the E-clip between the roller and the bushing above it.
A small amount of 100% silicone grease was applied to the uppermost bushing that sits in the base, above the spring (on both the outside of it where it rubs against the base, as well as the inside where it rides along the shaft.) I also like to put a toothpick tip's worth of grease on the top of the stick, were the shaft grinds against the base. The trick with these is to not overlube them and make a mess. Just use small amounts, and apply it with a toothpick only where it's needed. You don't want any down on the actuator, where it can contaminate the leaf switches.
The 4 screws for the lower plate were missing, but I looked through my spare parts to find four that fit. (I have no idea what size they are, but they fit.)
