I just finished running some hv ceramic feedthrus through the dishwasher (only the ceramic parts) a few times. cleans them up like new. gotta force dry them to make sure you dont have any dried water tracks on any unglazed portions, but the cleaning is great.
I think fully one half of any restoration project is spent cleaning. At least, if you're doing it right.
I'm going to be boiling up some breadslicers in acid when I get back home.
(down at my dad's place for 2 days)