[Kevin Kuehn]

Well you can turn the rotor so it's completely out of mesh from the stator - that eliminates any possibility of plates rubbing. You can disconnect the wire wound(grid stop) resistor and the RF transformer wire from the stator by removing the top and bottom nuts on the rear of the stator - that eliminates any possible leakage through those two points. Other than that you have the stator supported to chassis by the top and bottom phenolic insulators. I suppose there's a remote chance that something metallic is bridging across the phenolic pieces to chassis ground. I can't see any other possibly path to ground.