Thanks, guys. I cleaned up the knobs and they're in very nice shape.
Behind the channel knob is what appears to be a fine tuning lever, but I can't find any reference to it in either Sams or Riders. What's worse is that I can't figure out how to remove it. It's either very stuck, or I'm missing what's holding it on the shaft. Seems like it and it's bushing should pull straight forward from the inner tuner shaft. I'm going to try a little soak in WD 40. It's the only thing keeping me from removing the chassis. Any idea's?