Leave the feedthru capacitor plate where it is as you lift up and remove the entire grid compartment. Unscrew the nut that holds the tuning capacitor to the side wall of the compartment. Remove the capacitor and set aside, this will be modified and reinstalled. The input pedestal inductor has to be removed from the input cavity. This can be a real bear depending on the state of the set screws that hold the pedestal to the cavity at the cold end.
Extreme cases require drilling out the set screws.
Once the set screws are loosened, slide the pedestal out of the cavity and unscrew at the thread joint. Saw off an inch or so of the grid line to put back in the hole where the set screws are located. Plug the hole and tighten the set screws. The only component remaining in the grid compartment at this point should be the TNC RF input jack. This completes the removal process.