Philco 38-7 tuning mechanism

[comradesvox]

Hi. I am restoring a Philco 38-7 console radio. I have replaced the caps/resistors already. I am stuck on the cone-centric tuning mechanism. I cannot seem to engage the intermediate position so the inner tuning ring does nothing. I can only make this work in thte in or out position. I do remember trying to loosen the tuning knob so I could remove the chassis from the case - should not have done that. I hope I didn't break anything.

Also, is there any way you recommend cleaning the air capacitor plates without removing it?

Any advice would be greatly appreciated.