A series of light taps should be sufficient to back out the pin. If it is stubborn, use a fine file to remove the peened-over head at one end of the pin, and try again. Once the outer pin is out and safely retrieved, remove the tuning dial. Do this carefully - the dial is actually a flexible brass band wrapped around a cast pot metal framework, and the framework may have numerous splits and cracks. If it breaks when you remove it, your project will most likely be over.
Pot metal is virtually irrepairable.
Remove the inner lock pin and save it. Slide the inner bushing to the left, and remove the shaft from the bathtub. Clean all the parts, including the bathtub, in a solvent which will remove hardened grease and varnish. Use a soft paintbrush to work the solvent down between the rotor plates without bending them, and then repeat for the stator plates. If your unit is really dirty, each of the three stator sections can be removed from the bathtub and washed separately.